Phase 081 Report Final Version

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GVI Costa Rica

Coastal Rainforest and Wildlife Expedition

Phase Report 081

11th January 21st March 2008

Phase Report 081

11th January 21st March 2008


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GVI Costa Rica Coastal Rainforest and Wildlife Expedition Report

Submitted in whole to:Global Vision International

The Canadian Organisation for Tropical Education and Rainforest Conservation

(COTERC)Steven Furino, Waterloo University, Canada

Submitted in part to:The Ministry of Environment and Energy of Costa Rica (MINAE)

Produced byRebeca Chaverri - Country Director

James Lewis - Programme CoordinatorDavid Jones Base Manager

Diogo Verissimo Expedition StaffManuel Delgado Expedition StaffBrooke McIntyre Expedition Staff

Darren Watts Expedition InternCoraline Daeninck - Expedition Intern

And

Tom Bregman Expedition Member Simon Ferguson Expedition Member

Kristle Villemaire Expedition Member Christian Chavarria Expedition Member

Ian Quest Expedition Member Becky Solecki Expedition Member

Ruth Mattock Expedition Member Marie Errington Expedition Member

Scott Evans Expedition Member Ulla Koskinen Expedition Member

Ben Fisher Expedition Member Dannielle Price Expedition Member

Simone Du Toit Expedition Member Lynn Windell Expedition Member

Andrew McCreery Expedition Member James Weber Expedition Member

Kimberley Barylo Expedition Member Simon Crosbie-Smith Expedition Member

Peter Graham Expedition Member Amy Bloor Expedition Member

Sarah Cater Expedition Member Christina Hassett Expedition Member

Paul Rowntree Expedition Member Codie Gesumaria Expedition Member

GVI Costa Rica Coastal Rainforest and Wildlife Expedition

Address: Estacin Biolgica Cao Palma, Tortuguero, Costa RicaTel: (+506) 2709 8052Email: [email protected]

Web page: http://www.gvi.co.uk


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Executive Summary

The 11th ten-week phase (phase 081) of the Global Vision International (GVI) Costa

Rica Coastal Rainforest and Wildlife Expedition has now been completed. The

expedition, based at Estacin Biolgica Cao Palma (EBCP), has continued to worktowards the gathering of important environmental scientific data whilst working with local,

national and international partners and has maintained working relationships with local

communities through both English classes and local community events. The following

projects were conducted during phase 081:

Marine Turtle Monitoring and Conservation Programme. In collaboration with the

Canadian Organization for Tropical Education and Rainforest Conservation

(COTERC) and the Costa Rican Ministry of Environment and Energy (MINAE) andin association with the Caribbean Conservation Corporation (CCC).

Monitoring of Jaguar Predation on Marine Turtles. In collaboration with MINAE.

Jaguar Camera Trapping Study in Tortuguero National Park (TNP). In collaboration

with MINAE.

Large Mammal Monitoring Programme. In collaboration with COTERC.

Resident and Migratory Canal Bird Study. In collaboration with Steven Furino from

Waterloo University, Canada.

Estacin BIolgica Cao Palma Incidental Species Study Canal Boat Impact Study on Cao Palma canal.

English Language and Environmental Education lessons. In collaboration with the

San Francisco community and Tortuguero Canopy.


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Table of Contents

Executive Summary ........................................................................................................ 31 General introduction ................................................................................................ 82 Marine Turtle Monitoring and Conservation Programme ........................................ 11

2.1 Introduction .................................................................................................... 112.2 Aims .............................................................................................................. 122.3 Methodology .................................................................................................. 12

2.3.1 Study site ............................................................................................... 122.3.2 Pre-season preparations ........................................................................ 132.3.3 Data collection........................................................................................ 13

2.4 Results ........................................................................................................... 162.5 Discussion ..................................................................................................... 17

3 Monitoring of Jaguar Predation on Marine Turtles ................................................. 193.1 Introduction .................................................................................................... 193.2 Aims .............................................................................................................. 203.3 Methodology .................................................................................................. 20

3.3.1

Study site ............................................................................................... 20

3.3.2 Survey technique ................................................................................... 213.3.3 Data collection........................................................................................ 21


Jaguar Camera Trapping Study ............................................................................. 294 29

4.1 Introduction .................................................................................................... 294.2 Aims .............................................................................................................. 294.3 Methodology .................................................................................................. 30

4.3.1 Study site ............................................................................................... 304.3.2 Survey techniques .................................................................................. 304.3.3

Data collection........................................................................................ 32


5 Large Mammal Monitoring Programme .................................................................. 365.1 Introduction .................................................................................................... 365.2 Aims .............................................................................................................. 365.3 Methodology .................................................................................................. 37

5.3.1 Study site ............................................................................................... 375.3.2 Data collection........................................................................................ 37


6 Canal Bird Monitoring Programme ......................................................................... 406.1 Introduction .................................................................................................... 406.2 Aims .............................................................................................................. 406.3 Methodology .................................................................................................. 41

6.3.1 Study site ............................................................................................... 416.3.2 Data collection........................................................................................ 41


7 Incidental Species Study ....................................................................................... 507.1 Introduction .................................................................................................... 50


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7.2 Aims .............................................................................................................. 507.3 Methodology .................................................................................................. 50

7.3.1 Data collection........................................................................................ 507.4 Results ........................................................................................................... 507.5 Discussion ..................................................................................................... 52

8 Canal Boat Impact Study ....................................................................................... 538.1 Introduction .................................................................................................... 538.2 Aims .............................................................................................................. 538.3 Methodology .................................................................................................. 538.4 Results ........................................................................................................... 548.5 Discussion ..................................................................................................... 56

9 English Language and Environmental Education ................................................... 589.1 Introduction to English Teaching .................................................................... 589.2 Introduction to Environmental Education ........................................................ 589.3 Aims .............................................................................................................. 589.4 Methodology .................................................................................................. 59

9.4.1 Training .................................................................................................. 599.4.2 Teaching ................................................................................................ 59

9.5 Results ........................................................................................................... 609.6 Discussion ..................................................................................................... 6110 References ............................................................................................................ 64


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List of Figures

Figure 3-1 Number of green turtle full tracks (black) and half-moons (grey) recorded

weekly. Parque Nacional Tortuguero, Costa Rica. ........................................................ 25Figure 3-2 Number of leatherback turtle full tracks (black) and half-moons (grey)

recorded weekly along the 14.5 miles of beach in Parque Nacional Tortuguero, Costa

Rica. .............................................................................................................................. 25Figure3-3 Number of surveys where jaguar presence was detected between half mile

marker. Parque Nacional Tortuguero, Costa Rica. ........................................................ 26Figure3-4 Number and location of jaguar track entries and exits. .................................. 27Figure 6-1 Total number of species on Cao Chiquero, Cao Harold and Cao Palma,

Tortuguero, Costa Rica. ................................................................................................ 43Figure 6-2 Study species recorded per survey on Cao Chiquero aquatic trail, TNP,

Costa Rica. ................................................................................................................... 44Figure 6-3 Study species recorded per survey on Cao Harold aquatic trail .................. 45

Figure 6-4 Study species recorded per survey on the aquatic trails (AQT) entrance...... 46 Figure 6-5 Study species recorded per survey on Cao Palma, Costa Rica. ................. 47Figure 8-1 Proportion of tourism v non-tourism traffic passing EBCP. ........................... 55Figure 8-2 Comparison of the number of boats per Lodge recorded on Cao Palma. ... 55 Figure 8-3 Distribution of time of day and number of boats passing EBCP. ................... 56List of Tables

Table 3-1 Survey dates, intinerary/route and duration for walks conducted in Phase 081

...................................................................................................................................... 24Table 4-1 Position of camera sites along study site ....................................................... 33


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Table 4-2 Timeframe, unit(s) installed and number of records per study site ................. 33Table 4-3 Presence/absence of recorded species and there distribution across camera

sites .............................................................................................................................. 34Table 5-1 Number of records per ID method on BCWR, Costa Rica. ........................... 38Table 5-2 Number of individuals recorded per ID method .............................................. 39Table 6-1 Canal Bird Monitoring Study Species ............................................................ 42Figure 6-1 Total number of species on Cao Chiquero, Cao Harold and Cao Palma,

Tortuguero, Costa Rica. ................................................................................................ 43Table 7-1 Top incidentals and the percentage of days that they were recorded on over

the 78-day period, Estacin Biolgica Cao Palma, Costa Rica. ................................... 51Table 7-2 Top incidentals by order, Estacin Biolgica Cao Palma, Costa Rica .......... 51 Table 8-1 Boat use restriction on Cano Palma, Tortuguero, Costa Rica. ....................... 53 Table 9-1 Topics covered throughout the phase for each of the formal classes ............. 60


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1 General introduction

Global Vision International (GVI) was formed in 1998 to provide support and services to

international charities, non-profits and governmental agencies, through volunteering

opportunities and direct funding. GVI is guided by a unique commitment to its volunteersand to its partners. To the volunteer it offers a safe responsible travel experiences,

exceptional training and career development opportunities, and facilitates the ability to

make a real difference. To its partners it commits all research ownership rights and all

work is undertaken under their direction, in conjunction with the local community. In July

2006, GVI established the Costa Rica expedition based at Estacin Biolgica Cao

Palma (EBCP), Tortuguero.

The biological station is located in the southern section of the Barra del Colorado WildlifeRefuge (BCWR) directly to the north of Tortuguero National Park (TNP). The area of

operation for the expedition covers both TNP and the BCWR; both of which are included

in the Tortuguero Conservation Area (ACTo). The area consists of a collection of

waterways running through Caribbean lowland rainforest. The coastal habitats are

generally similar in type throughout the area of operation with small variation in boarding

habitats, width of the beach and quantity and type of debris found on the beach. The

forest habitats vary more considerably with several distinct habitats being present.

Altitudinal differences of a couple metres have a large effect on both habitat and speciescomposition in the area. Lower areas, such as those found around the station, tend have

large areas of flooded forest whereas the drier areas associated to the national park

tend to only be submerged during times of flooding. Within ACTo there are also areas

containing higher ground of up to 311m in Lomas de Sierpe. Most of the research is

carried out within TNP and BCWR, where the highest elevation is El Cerro (119 meters

above sea level). Although these are not particularly high they do provide non-floodable

habitat. The ecological importance of the ACTo has been recognized for some time;

however, the level of active research has been minimal aside from the world-renowned

turtle studies.

The EBCP was purchased in 1991 by the Canadian Organization for Tropical Education

and Rainforest Conservation (COTERC). The stations research was intended to focus

on terrestrial ecology studies leaving the monitoring of the turtle population to the

Caribbean Conservation Corporation (CCC). Prior to GVIs arrival a number of studies


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had been undertaken looking at various species and habitats but no longer term

monitoring projects had been possible.

GVIs volunteer resource made long-term studies possible and needs were assessed

and partnerships sourced. Currently GVI is working closely with MINAE, COTERC,Waterloo University, the local community of San Francisco and the CCC.

Along with the individual needs of partners, GVI seeks to meet several of its own aims

when undertaking work in an area. These aims are:

Document biodiversity of the area

Increase scientific knowledge

Encourage scientific interest in the area

Increase community awareness and capacity building

Support sustainable development.

The Tortuguero area has been of strong interest to the scientific community since Archie

Carrs studies of the Marine Turtles of Playa Tortuguero during the 1950s. Archie Carr

highlighted the importance of this stretch of coast for green turtles (Chelonia mydas) and

his work promoted the TNP establishment in 1975 (Boza & Mendoza 1981).

Being a large charismatic species, green turtles tend to attract both researches andtourists: data collected by MINAE has shown a steady increase in the number of visitors

each year to Tortuguero (Bermdez & Hernndez 2004a, Allan Valverde pers. comm.

2007). Although many visitors come specifically to see the turtles, others visit TNP for its

canals and abundant wildlife. Often referred to as the Amazon of Costa Rica, Tortuguero

offers visitors a chance to view wildlife from both boats and on foot.

The impact of this human presence is becoming more obvious within ACTo. Lodges are

in need to expand and as a result they are consuming more forested areas; new homes

are being built for the workers of these hotels and associated industries; and an increase

in demand for building materials and general goods is resulting in increased use of the

canals. Areas that had previously not been visited by tourists are now beginning to open

up and although some limits are being put in place to control tourist numbers in certain

locations, many areas are uncontrolled and not monitored.


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As tourism has increased so has job availability and as a result the population of

Tortuguero has increased and new settlements have developed. The most significant

new settlement has been the establishment of the San Francisco community. San

Francisco began its history as a home to a few families in 1989. It was not until 2000 that

the population began to increase more significantly. Now San Francisco is home to 274people and this number is continuing to increase (Van Odenhoven 2007).

San Francisco is increasing in size almost constantly and as a result is having an

obvious impact on the local environment. This increased demand on local resources is

demonstrating the need for management of both TNP and the BCWR as well as the

importance of the monitoring programme on Playa Norte.

The projects currently being run by GVI in ACTo aim to help raise awareness of the

effect these changes are having on the environment. This is being done in numerous

ways some of which have a direct effect on the conservation of the area whilst others

have longer-term educational benefits.

This report briefly looks at the work undertaken during Phase 081 (11 th January 21st

March 2008). Its aim is to present an outline of the specific aims, methodologies and

results gained during this period. In some cases, such as the turtle-monitoring

programme, season reports are produced and therefore no results have been included.

In addition to this report, a year report is produced annually presenting in more detail

findings from the year and in some cases comparing to previous years work. Throughout

this document, those persons who have received additional training in order to be able to

train and lead others on surveys are referred to as Research Staff (RS) or Patrol

Leaders (PLs), as appropriate. Persons trained to assist the RS in all aspects of their

work are referred to as Research Assistants (RAs).


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2 Marine Turtle Monitoring and Conservation Programme

2.1 Introduction

Over the past 20 years, there has been an extensive decline in marine turtle populations

worldwide due to illegal harvesting of meat and eggs, unsustainable fishing practices,water contamination, and habitat destruction. As a result, the World Conservation Union

(IUCN) lists all marine turtle species as either endangered or critically endangered

(IUCN, 2006).

Having six out of the worlds seven species of marine turtles, not only is Central America

known for diversity but also for the large number of marine turtle nesting on its beaches.

Within this sub-continent, Costa Rica hosts some of the largest populations of

leatherback (Dermochelys coriacea), green and olive ridley (Lepidochelys olivacea)turtles, assuming a pivotal role in marine turtle conservation.

Two years after its creation in 1990, COTERC was approached by the CCC with a

proposal of monitoring the marine turtle population on Playa Norte (Greg Mayne written

comm 2007), the beach to the north of Laguna Tortuguero. Between 2004 and 2005

COTERC undertook a feasibility study in order to establish the significance of the nesting

site on Playa Norte and to assess whether the number of marine turtles warranted a

programme (Greg Mayne written comm 2007). Playa Norte adjoins the aforementioned

community of San Francisco, currently borders two hotels, Cabinas Vista al Mar and

Turtle Beach Lodge, approximately eight private homes and there are plans for a larger

hotel within the survey area. Existing just north of the boundary of the National Park it

has gone without the regular law enforcement and protection afforded to Playa

Tortuguero for decades.

Based on the findings of the preliminary study, in 2005 a marine turtle monitoring and

conservation programme was implemented and initiated, with the assistance of GVI in

2006.

This report is a summary account of the work developed and data collected from 11 th

January to 17th March 2008.


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2.2 Aims

The overall aims of this programme are to monitor the population dynamics of marine

turtles on Playa Norte and investigate the impact of human activities on their

conservation status.

In terms of species conservation the programmes aims are to 1) reduce poaching rates

by constant presence on the beach, disguising and relocating nests as necessary, 2)

educate the community and tourists about marine turtle conservation and 3) manage the

beach habitat as to increase availability of nesting sites 4) investigate the impact of

human development on the marine turtle population

In terms of species monitoring the programmes aims are to 1) gather selected biometric

data on nesting marine turtles, 2) record the spatial and seasonal distribution of nesting

turtles, 3) monitor the number of nesting emergences, 4) determine the level of illegal

poaching on turtles and their nests, 5) record survival of the nests and hatchling success

rates, 6) monitor for the apparent physical health of nesting females, 7) track re-

emergences to the nesting beach and or migration between beaches, and 8) register

tourist and human development around the nesting site.

2.3 Methodology

The methodology used for the marine turtle-monitoring programme follows the

GVI/COTERC protocols. For further, more specific methodologies, please refer to the

2008 Marine Turtle Conservation and Monitoring Programme Night and Day Protocols.

Furthermore, a logical framework for the programme was designed in March of this year

to maintain the objectives and aims through time and allow evaluation of management

practices at the end of the season.

2.3.1 Study site

The sand on Playa Norte is black and fine, typical of a high energy-beach. The width of

the nesting beach platform, or berm, varies from two to 38 meters, but the configuration

of its shape and size changes constantly in response to long shore drift and exposure

levels.


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The dominant plants on the nesting beach are morning glory (Ipomoea pes-caprae), rea-

purslane (Sesuvium portulacastrum) and rush grass (Sporobolus virginicus). The berm is

bordered by a hedgerow of cocoplum (Chrysobalanus icaco) and sea grapes (Coccoloba

uvifera) with a mixture of coconut palms (Cocos nucifera) and various tropical

hardwoods behind.

Playa Norte, which contains the study area of 31/8 miles long (approximately 5 km),

extends from the Tortuguero River mouth (N10 35.673 W83 31.495) on the southern end

of the beach to Laguna Cuatro (N10 38.115 W83 32.528) to the north. Although this

beach is not located within the TNP boundaries, it is situated adjacent to the BCWR,

which, like the TNP, is managed by ACTo under the MINAE.

The study area is marked as mile marker (MM) 0 at the Tortuguero River mouth and MM

31/8 just north of Laguna Cuatro. The length of the beach is divided and marked with mile

markers at every eighth of a mile (approximately 200 m), to allow for the documentation

of spatial distribution and density of nests along the beach.

The nearest village to the study site is San Francisco, situated south of MM 0. On the

southern side of the Tortuguero river mouth is Playa Tortuguero, which the CCC

monitors from MM -3/8 to Jalova lagoon at MM 18.

2.3.2 Pre-season preparations

Before the season began, each mile marker was repaired or replaced if necessary. Each

volunteer and patrol leader was trained thoroughly both in the classroom and in the field

in order to ensure competent data collection and ethical behaviour on the beach. At the

end of the training, all Research Assistants (RAs) and Patrol Leaders (PLs) were

submitted to a test. For RAs the passing mark was 95%. Patrol Leaders were subject to

more intense and thorough training with corresponding testing, for which the passing

mark was 100%.

2.3.3 Data collection

Daily track census and nest surveys


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A track census and nest survey was conducted every day from 22nd February to 17th

March. It started between 5:00 and 6:00 am, depending on the specific time of sunrise,

and lasted up to two and a half hours depending on the volume of data to collect and the

need to disguise nests or tracks. The survey involved walking the beach between MM 0

and MM 31/8, recording and monitoring tracks and nests from the night before. Thesurvey team identified tracks as nests, half moons (non-nesting emergences) or a lifted

turtle (no tracks going back into the sea).

All tracks not seen the night before were documented using Global Positioning System

(GPS) coordinates, the northern mile marker and vertical position. The nests seen by the

night team the previous night were monitored on the two days after they were first

discovered and identified as natural, poached, predated or unknown (if the nest had

many signs of poaching, such as an accumulation of flies, stick holes, and human and ordog prints, but no egg shells or cavity).

Night surveys

Night surveys were conducted every night from 29th February to 17th March. Each night

at least one survey team walked the study area a minimum of four hours. If one team

was on the beach they patrolled around 22:00 to 02:00. When two teams patrolled, the

first team patrolled the beach from approximately 20:30 to 00:30 whilst the second team

patrolled from 23:00 to 03:00.

When a turtle track was found, the PL determined whether or not the turtle was still on

the beach. If not, the PL determined if the track was a half moon, nest, or lifted turtle. If it

was deemed a half moon, the species, GPS coordinate, closest Northern mile marker,

and time track was seen were all recorded. If deemed a nest, the species, GPS

coordinate, closest Northern mile marker, time the track was seen, vertical position, and

nest status were recorded. If deemed a lifted turtle the species, GPS coordinate, closest

Northern mile marker, time the track was seen and vertical position (if it had nested),were recorded.

When a turtle was encountered, the PL tried to determine what stage of the nesting

process she was in (emerging, selecting a nest site, digging a body pit, digging the egg

chamber, oviposition, covering the egg chamber, disguising the nest or returning to sea).


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All patrol members who were to come in contact with the turtle put on gloves. Once the

egg-laying process had started, the eggs were counted (yolkless and fertile counted

separately) and triangulation of the nest was completed. When the turtle completed

oviposition and began to cover her egg chamber, she was then checked for tags, Old

Tag Notches (OTNs) and Old Tag Holes (OTHs) and tagged if necessary. Leatherbackturtles were tagged in the thin skin between the rear flippers and the tail using Monel #49

tags (National Band & Tag Co., Newport, USA). Green turtles were tagged on the front

flippers before the first scale using Inconel #681 tags (National Band & Tag Co.,

Newport, USA).

Once tagging, was finished, and if appropriate, the minimum curved carapace length

(CCLmin) and maximum curved carapace width (CCWmax) were taken to the nearest

millimetre, three times each. If the measurements were not within three millimetres ofeach other more were taken until the data was consistent. For leatherbacks, CCLmin

was taken from the nuchal notch where the skin touches the carapace, along the back to

the right of the central ridge until the end of the caudal projection. It was also noted

whether the caudal projection was complete or not. For green, loggerhead (Caretta

caretta), and hawksbill (Eretmochelys imbricata) turtles, CCLmin was taken from where

the skin touches the carapace along the back until the posterior notch (not the longest

length of the carapace). For all species, CCWmax was always taken along the widest

part of the turtle.

Once tagging and measurements were completed, the turtle was checked for bite marks,

abnormalities and fibropapillomas tumours. All abnormalities were recorded.

The GPS coordinates of the egg chamber, closest northern mile marker, stage the turtle

was encountered in, encounter time, direction whilst nesting, and vertical position were

also recorded.

Nest fate, nest survivorship and hatching success

Nests were triangulated during oviposition whenever possible in order to gather as much

information about the poaching rate and hatchling success as possible. Triangulation

was done in order to enable the excavation of the nests 70 days after the nest was laid

for green turtles or 75 for leatherback turtles. Triangulation was conducted using three


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pieces of flagging tape that featured the direction (north, centre, and south) and the

station name. These were attached to the vegetation behind the nest. The distance from

the centre of the egg chamber to each of these tags was measured to the nearest

centimetre whilst the turtle was laying eggs. The distance to the most recent high tide

line was also recorded. Three triangulation points were used to compensate for the lossof any points of reference: if one point is lost it is still possible to locate the nest using the

other two points.

Disguising nests

For all leatherback nests, considerable effort was put into disguising the nests from

poachers. Several strategies were used, such as erasing the tracks with a long piece of

wood, throwing dry sand all over the area, sweeping the sand with a coconut leaf,

placing logs and other debris on top of the nest and remove them later, etc. For green

turtles, although the body pit was always obvious, some disguising efforts, like erasing

the tracks, were also put into place.

Collection of human impact data

During each night survey, the number of red and white mobile lights, fires, locals and

tourists on the beach were recorded. Furthermore, each month during the new moon the

number of stationary white and red lights were also recorded.

Habitat management

Sixteen beach cleans were completed this phase to increase the availability of nesting

sites. After mid-phase a new management scheme was implemented where the morning

census teams evaluated the condition of each eighth of a mile of the study area and

passed that information to the beach clean teams as to allow for more effective beach

cleans.

2.4 Results

During phase 081, 25 morning surveys and 34 night surveys were completed. A total of

78 miles were walked on morning surveys and 272 miles were walked on night surveys.


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The first nest was observed on the 22nd of February with ten leatherback turtles nests

and one half-moon recorded during the survey period. Of this number, five leatherback

turtles were encountered; three had existing tags in place and two were tagged by the

project.

Of the 10 leatherback nests recorded, nine were classified as natural whilst one was

deemed unknown due to the presence of stick holes, human footprints and disturbed

sand. Nesting activity was highest between MM 2 and MM 21/8. Most encounters

occurred between 23h30 and 23h45.

Two green turtle nests were recorded, with one of the nesting turtles having been

tagged. The first nest was found on the night survey of the 11th of March. Both nests

were classified as natural. Nesting activity was highest between MM 6/8 and MM 7/8. The

only turtle encountered for this species occurred at 23h40.

This phase a pilot study examining activity beyond the northern extent of the current

study area was initiated. On one occasion, the morning census team continued north

along Playa Norte for an additional 1.5 miles. The team observed only an old poached

leatherback nest on the 8th of March, which was assumed to be a week old based on the

condition of both track and nest.

In addition to the above information, morning team on the 28th

February found adeceased juvenile hawksbill (CCL 4.5 cm; CCW 3.5 cm) washed up just south of mile

marker 3 1/8. The cause of death could not be determined.

2.5 Discussion

Since the data collection from this phase only covers the very beginning of the nesting

season for leatherback turtles, this is only preliminary data for this year.

One important observation however, is that both leatherback and green turtles havebeen recorded as nesting earlier on Playa Norte this year in comparison to 2007. Last

year morning surveys began in same date and during the same period we registered

only two leatherback nests, the first of which was on the 15 th of March, and no green

turtle nests.


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Although only one survey was conducted beyond Laguna Cuatro during this phase, our

findings are that marine turtle activity is lower north of the study area. During phase 082

(from the 11th of April to the 19th of June), this monitoring will be conducted weekly to

improve our understanding of the nesting marine turtle population using that area,

together with the associated human impact.


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3 Monitoring of Jaguar Predation on Marine Turtles

3.1 Introduction

The only species that are known to kill adult marine turtles are sharks (i.e. Carcharhinus

leucas, Carcharodon carcharias and Galeocerdo cuvier), orca (Orcinus orca), crocodiles(Crocodylus acutus and C. porosus) and jaguars (Panthera onca) (Hirth, 1997; Ortiz et

al., 1997 in Trong 2000). Information on jaguar predation of marine turtles has been

recorded sporadically in different areas of the Neotropics.

At least eighty two green turtles, three leatherbacks and seven olive ridley were

identified as being predated by jaguars in Suriname from 1963-1973. In 1980, 13 green

turtles were killed within only a few days close to this nesting beach (Autar, 1994).

Koford (1983) mentions that jaguars prey on marine turtles in Costa Rica, although no

specific species are mentioned. On the Pacific coast of this country, jaguars have been

recorded preying upon olive ridley, black (Chelonia mydas agassizii), and hawksbill

turtles (Carrillo et al., 1994, Chinchilla, 1997). Although much research has been carried

out on turtles in TNP, data collection methods on jaguar predated turtles in TNP has

been inconsistent. From 1971 the CCC began regular track census along Playa

Tortuguero. Before 1997 only two green turtles were recorded as being killed by jaguars,

one in 1981 (Carrillo et al., 1994) and another in 1984 (J. Mortimer pers. comm. in

Trong 2000).

In 1997, the CCC began collecting specific information on turtles predated by jaguars

during their weekly track censuses (Trong 1997, CCC 1999). That year, four green

turtles killed by jaguars were recorded, both fresh and old kills (Trong 1997). During

1998 and 1999 only fresh kills, i.e. those killed within the last 24 hours were recorded. In

1998, 25 dead green turtles were found, and in 1999, 22 green and two leatherback

turtles were found (Trong, 2000). In 2002, Magally Castro Alvarez, in conjunction with

MINAE and WCS began a study on the predation of marine turtles by jaguars in TNP.

Castro Alvarez recorded all kills, both fresh and old. In 2002, 60 turtle carcasses were

encountered, and in 2003, 65 (M. Castro Alvarez, unpublished data).

In 2005, MINAE invited GVI to continue data collection on jaguar presence and

predation of marine turtles in TNP on their behalf. GVI began data collection on 11th July


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2005, modifying the MINAE protocols in line with agreed aims and available resources.

The study found 60 turtle carcasses from July to December 2005 and 131 turtles in the

first full year, 2006. In 2007, 144 dead turtle carcasses were recorded as jaguar quarry.

Though predation upon turtles by jaguars is not a new phenomenon, from the CCC andMagally Castro Alvarez studies it can be inferred that the level of predation has been

increasing over the past years within TNP, but the magnitude of this apparent increase

may be due to changes in data collection methods. Trong (2000) counted only fresh

carcasses with evidence of jaguar predation for two out of the three years of his study,

whilst Castro Alvarez study considered all carcasses with no contrary evidence to be

jaguar predated.

These studies identified a phenomenom within Playa Tortuguero and GVIs personnel

carry regular surveys with an established methodology and aims at conducting them

over a greater period, in order to understand its implications on a larger scale

3.2 Aims

This project aims to 1) document the magnitude of jaguar predation on the nesting

population of marine turtles and 2) increase knowledge of jaguar ecology in Tortuguero

National Park.

This information can be used to help MINAE develop management strategies which

cross the multiple habitats contained within the National Park, benefitting both the turtles

and the jaguars.

3.3 Methodology

3.3.1 Study site

The beach of TNP, which contains the study area, is 18 miles long (approximately 29

kilometres), and extends from the Tortuguero River mouth on the northern end of thebeach to the Jalova River mouth at the Southern end. The park is managed by ACTo

under MINAE.

The study area is mile 34/8 at the southern border of Tortuguero village to mile 18 at the

Jalova river mouth. The length of the beach is divided and marked with mile markers at


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every eighth of a mile (approximately 200 meters) until mile 5, and is marked at every

half mile thereafter. The mile markers run in ascending order from mile 0 at the

Tortuguero River mouth to mile 18 at the Jalova river mouth.

During the marine turtle nesting seasons, there is a high level of human activity betweenmile 0 and mile 51/2 of Playa Tortuguero. This area is the focus of the CCCs marine

turtle work where they conduct one morning survey and two night surveys per day in

season; it also hosts a large number of tourists on turtle watching tours. At the southern

end of the study site is a large cattle and coconut farm. These areas of human activity

may affect jaguar behaviour.

3.3.2 Survey technique

Weekly surveys were conducted over the 14 mile study site, beginning at dawn. For

the first half of the phase, one team surveyed the entire study site, alternating between a

north start at mile 34/8 (Tortuguero) and a south start at mile 18 (Jalova) when possible.

The second half of the phase utilised two teams per survey; Team One started from mile

34/8 and surveyed to mile 11. Team Two began at mile 18 and also surveyed to mile 11.

The average team consisted of one RS and three RAs collecting the data outlined

below.


General data

For each survey, the following general information was recorded:

Research team initials

Starting point (Tortuguero or Jalova)

Start and end time

Weather data (recorded at mile markers 4, 8, 12 and 16): time, sand condition (dry,

moist, wet), percentage cloud cover, precipitation (none, light, medium or heavy) and

beach width (measured from the mile marker to the high tide line)

Comments e.g. jaguar tracks not clearly visible due to a very high tide

Turtle track data


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Marine turtle carcasses were recorded as jaguar predated if no contradictory evidence

was present. The following data was recorded on all jaguar predated marine turtles

where relevant:

Species (leatherback, green, hawksbill or loggerhead) Turtle ID number (species initials and record number for the season e.g. Cm001)

Locality (distance from Northern mile marker and GPS coordinates)

Vertical position (open, border or vegetation)

Point of attack

Parts of turtle eaten by jaguar

Estimated number of nights since kill (determined by signs of decay)

Curved carapace length (CCL)

Whether the turtle was resting on its plastron or carapace (front or back)

Any other comments e.g. drag marks, jaguar prints near the carcass, high vulture

activity, tag numbers

Due to rapid rates of decay and the activity of scavengers, point of attack, parts eaten

and CCL were recorded on fresh cadavers only (within 1-2 days). Photographic records

were taken for evidence of predation, turtle identification and location. These records

also provide an additional method of ensuring against double counting.

3.4 Results

Eight surveys were conducted between the 20 th of January and the 9th of March 2008.

Three surveys were completed from Tortuguero to Jalova, one from Jalova to

Tortuguero. Four surveys were completed utilising two research teams.

The average duration of the surveys completed when using one research team was eight hours and

10 minutes. The average duration of the surveys completed by Team One was five hours. The

average duration of the surveys completed by Team Two was four and a half hours (

Table 3-1).


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Table 3-1 Survey dates, intinerary/route and duration for walks conducted in Phase 081, Playa Norte,

Refugio de Vida Silvestre Barra del Colorado, Costa Rica.

One hundred-and-one full turtle tracks were recorded for the phase: 80 green and 21

leatherback. Eleven half-moons were recorded, seven green and four leatherback. No

full turtle tracks were recorded before the forth week of survey (10 th of February). Week

eight (starting on 9

th

of March, 2008), recorded the highest number of full turtle tracks; 31green and 16 leatherback tracks (Figure 3-1 and Figure 3-2).

Date Itinerary/Route Duration (hrs)

20-Jan-08 Tortuguero Mile 11 06:40

26-Jan-08 Jalova - Tortuguero 09:00

03-Feb-08 Tortuguero - Jalova 08:50

10-Feb-08 Tortuguero - Jalova 08:05

17-Feb-08 Tortuguero Mile 11 03:55

17-Feb-08 Jalova Mile 11 04:00

24-Feb-08 Tortuguero Mile 11 06:00

24-Feb-08 Jalova Mile 11 05:00

02-Mar-08 Tortuguero Mile 11 04:40

02-Mar-08 Jalova Mile 11 04:00

09-Mar-08 Tortuguero Mile 11 05:2009-Mar-08 Jalova Mile 11 04:55


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0

5

10

15

20

25

30

35

Week 1 Week 2 Week 3 Week 4 Week 5 Week 6 Week 7 Week 8

Week of survey

Numberoffullturtletracksand

halfmoon

s

Figure 3-1 Number of green turtle full tracks (black) and half-moons (grey) recorded weekly. Parque

Nacional Tortuguero, Costa Rica.

0

2

4

6

8

1012

14

16

18

Week 1 Week 2 Week 3 Week 4 Week 5 Week 6 Week 7 Week 8

Week of survey

Numberoffullturtle

tracksand

halfmoons

Figure 3-2 Number of leatherback turtle full tracks (black) and half-moons (grey) recorded weekly

along the 14.5 miles of beach in Parque Nacional Tortuguero, Costa Rica.

Two green turtles were recorded as jaguar predated during the survey period around

M10. One was recorded in week seven and one in week eight. No leatherbacks were

recorded during this period.


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Seventy-eight jaguar track sets were recorded during the survey period. Jaguar activity

spanned along the entire length of the survey site with over 80% of tracks found

between miles 5 and 5 4/8, mile 8 to 12 and 154/8 to 16. Between miles 8 and 9, jaguar

tracks were present on every walk (Figure3-3).

01

2

3

4

5

6

7

8

3.5 4.5 5.5 6.5 7.5 8.5 9.5 10.5

11.5

12.5

13.5

14.5

15.5

16.5

17.5

Distribution

Num

berofwalkswherejaguar

trackswerepresent

Figure3-3 Number of surveys where jaguar presence was detected between half-mile marker. Parque


The majority of the jaguar tracks were recorded in the mid-section of the study site,between miles 8.5 and 12.5; seven entry points onto the beach and five exit points were

recorded (Figure3-4).


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0

0.5

1

1.5

2

2.5

3.5 4.5 5.5 6.5 7.5 8.5 9.5 10.5

11.5

12.5

13.5

14.5

15.5

16.5

17.5

Nearest northern mile marker

NumberofExit

sandEntries

Entry

Exit

Figure3-4 Number and location of jaguar track entries and exits. Parque Nacional Tortuguero, Costa

Rica.

3.5 Discussion

In the corresponding period in 2007 there were no records of jaguar predated marine

turtles. This year there are records of two green turtles predated by jaguar during a

period of over 600% greater green turtle activity on the beach between the same periods

of January-March, rising from only 13 in 2007 full tracks to 80 in 2008.

Both of the records of jaguar predated marine turtles were encountered by the research

teams in the vegetation near mile 10. The second encounter displayed additional

evidence of jaguar activity (blood pools and drag marks) suggesting predation occurred

on the beach and feeding in the vegetation.

Jaguar activity has been recorded consistantly along Playa Tortuguero outside of the

nesting season both in phase 074 and now 081. No evidence of marine turtle activity

was documented on Playa Tortuguero this year until the 10 th of February, whereas

jaguar activity was in evidence on every survey conducted for this year, prior to and

since the emergence of nesting marine turtles.

Over the course of the phase, jaguar activity was recorded at each half mile of the study

site, indicating jaguars are ultilising the entire area to greater or lesser extents,

regardless of marine turtle activity.


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Seven sites of jaguar entry and five of exit between the forest and beach were identified,

at the extremes of the study site and concentrating in the centre. As the Jaguar Camera

Trapping Study (Chapter 4) becomes established, these two programmes are becoming

increasingly amalgamated. Entry/exit data, together with marine turtle carcass spatial

distribution data is utilised in the management of the trapping study when consideringcamera site location.

The full dataset of the programme thus far (2005-2008) is currently being analysed for

the first time in combination. A full report is to be compiled to evaluate trends, investigate

mitigating factors and discuss the significance of jaguar predation of marine turtles on

Playa Tortuguero.


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4 Jaguar Camera Trapping Study

4.1 Introduction

The jaguar (Panthera onca) is the third largest felid in the world and the largest in all of

North and South America (Silver, 2004). Its range used to span from the SouthwesternUnited States of America to Northern Argentina (Seymour, 1989). However, the current

known, occupied range is about 54% what it was in 1900 (Sanderson et al., 2002),

ranging from northern Mexico to northern Argentina and are considered threatened

across much of this range (Aranda 2000, Sanderson et al., 2002).

The jaguar is an elusive animal that has been hunted greatly in the past for its pelt

(Weber & Rabinowitz 1996). In 1968 alone, more than 13,000 pelts were imported to the

USA (NatureServe, 2006). Today the major threats to the jaguar are illegal hunting, preydepletion, and habitat destruction and fragmentation (Silver et al., 2004, Miller &

Rabinowitz 2002). Scientists have started to focus on a range-wide approach to the

conservation of the species. In order to aid future conservation initiatives of the species a

greater understanding of jaguar population dynamics is needed (Sanderson et al. 2002).

Little is known about the population of jaguars in TNP. The National Park guards have

seen jaguars on numerous occasions and have estimated that there are at least five

individuals currently using the beach (Eduardo Chamorro comm. pers. 2008). GVI has

initiated the use of cameras to estimate the population size of jaguars in the parks

coastal habitat.

Cameras have been used before to study secretive carnivore species such as tiger

(Panthera tigris) populations in India (Karanth & Nichols 1998, Karanth & Nichols 2000,

Karanth et al., 2004), and jaguar populations in the Neotropics (Silver 2004, Silveret al.,

2004, Salom-Prez et al., 2007). We have adopted similar methods as used by Silveret

al., (2004) and are currently undertaking field trials.

4.2 Aims

The aim of this project is to estimate the minimum number of jaguars using the coastal

habitat inside Tortuguero National Park. This requires the identification of individual

animals. The objectives are 1) to determine the areas where jaguars are present, 2) to


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record their hours of activity and other habits, 3) to compare jaguar activity at different

sites along the coastal forest.

4.3 Methodology

4.3.1 Study site

TNP beach is described in detail in section Error! No se encuentra el origen de la

referencia. There is a trail parallel to the beach running from mile 0 to mile 15, known

locally as Sendero Jaguar. Along the trail close to Tortuguero there are many paths that

lead to the beach, slowly becoming more dispersed the further South you travel. Tourists

use the trail between miles 0 and 6 frequently during green turtle season (June to

November). During off-season tourists and local people use the trail much less.

4.3.2 Survey techniques

Location of cameras

Camera sites were selected in the forest along the edge of the TNP beach based upon

data collected by GVI on location and number of jaguar tracks and jaguar predated

marine turtles. This data has been recorded for over two years during Jaguar Predation

on Marine Turtles surveys (see section 3).

Many factors were considered before selecting a camera site such as jaguar and human

presence, vegetation cover, trail width, and indirect sunlight. Ideally, the cameras sites

are placed no more than two miles apart, minimizing the possibility of unmonitored area

for a jaguar to pass through. When possible, cameras were placed on trails that are not

used often by humans, in order to avoid theft and photos of humans.

Setting the cameras

Two models of motion activated cameras were trialled simultaneously this phase: theMC2-GWMV Stealth Cam and DS-06 Camtrakker. The features of both cameras are

described below:

MC2-GWMV Stealth Cam


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The Stealth Cams are motion-activated, 32mm film cameras. They have a time-out

function. This means they can be programmed to pause from one to 60 minutes between

motion detection. Determining an appropriate amount of time depends on the level of

activity in the given location. This function was set for one minute, in order to capture

as many animals as possible within a short period of time.

The cameras also have a continuous capture feature. The cameras can be programmed

to take between one and nine pictures each time motion is detected. During this stage of

the study, the cameras were set to take three photos each time motion was detected.

After setting the cameras functions, a tampon was placed inside the casing to absorb

excess moisture; the unit was then sealed with duct tape and silicone sealant.

DS-06 Camtrakker

The Camtrakkers are heat and motion-activated digital cameras. They were set on high

sensitivity and with a ten-second delay to take two pictures each time motion was

detected. The date and time of activation was automatically recorded. A silicone sachet

was placed inside the casing and cameras were secured to trees with a chain or cable.

Both types of camera were set up off the trail, in a location where a jaguar might be

expected to pass. Trapping stations of two cameras per site were used, one camera wasset on the time function and the other one on the date function. Since the purpose is to

use the animals flanks for identifications, both sides must be pictured (Silveret al., 2004,

Karanth & Nichols 2000). Cameras were secured to trees two to four meters apart, at a

height of 30-60 cm above the ground (Silveret al, 2004).

Once a location was chosen and the cameras secured, they were directed at each other

and sticks were used to adjust the angle of the camera sight to 30 to 60 cm from the

ground. After setting the cameras, a tampon or silica gel packet was placed inside the

camera case to absorb moisture. As problems of water seepage have been encountered

whilst using the Stealth Cams, silicone sealant and duct tape were used to close all

seams and prevent water from entering. A few drops of feline bait, Wildcat #2, was

placed on a log or coconut husk between the cameras in an attempt to attract any

jaguars in the area to the exact camera location.


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Checking the cameras

The cameras were checked once every two weeks to minimise human disturbance of the

camera sites. At this time the film/memory card and/or batteries where replaced as

necessary and cameras checked for proper functioning. When several photos had beentaken (minimum of 9 non-test photos), or the cameras were non-functional, they were

removed and replaced. The film was then removed in a dark room in order to prevent

any overexposure when films did not completely rewind. All films were labelled with the

camera location, name and date. Digital photographs were saved into the database and

labelled by site location.


The following information was recorded for each camera site:

Site number

Nearest northern mile marker,

GPS co-ordinates

Physical description of the site

Date of first instalment

The following information was recorded when a camera site was checked, installed orremoved:

Site number

Date

Survey team initials

Camera numbers

Number of photos taken and species recorded on each camera

Action taken with each camera i.e. checked, installed or removed Problems encountered and any other relevant information (e.g. number of test

photographs registered).


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4.4 Results

Camera sites were distributed along the beach with varying degrees of success. In total

41 one photographs of animals were achieved, all recorded on the digital DS-06

Camtrakker model of camera trap.

SiteNumber(Linear)

NearestNorthern MileMarker Location (GPS coordinates)

GVI SiteCode

1 7 N:1029'24.3 W:832832.8 42 8.5 N:1028'15.4 W:833275.5 153 10 N:1027'09.0 W:832715.0 184 14 N:1024'04.4 W:832522.4 145 15 N:1023'38.8 W:832503.9 166 15 N:1023'24.4 W:832453.9 3

7 16.5 N:1022'41.9 W:832424.1 2

Table 4-1 Position of camera sites along study site. Parque Nacional Tortuguero, Costa Rica.

SiteDate ofinstalment

CamerasPresent Days in field

# ofrecords

129-Jan-08; 28-Feb-08

GVI01, CT01;CT04 30; 14 36

2 19-Jan-08 GVI12 & GVI02 27 03 02-Mar-08 CT03 7 14 20-Jan-08 GVI07, GVI11 21 0

5 10-Feb-08 GVI11, GVI07 14 06

03-Feb-08; 17-Feb-08 GVI03; CT02 13; 22 4

7 26-Jan-08 GVI10, GVI04 21 0

Table 4-2 Timeframe, unit(s) installed and number of records per study site. Parque Nacional

Tortuguero, Costa Rica.

Species

Presence (1) / Absence (0)

Site1

Site2

Site3

Site4

Site5

Site6

Site7

Site8

Central American agouti(Dasyprocta punctata) 1 1 0 1 0 0 1 0

Gray four-eyed opossum(Philander opossum) 0 1 0 0 0 0 0 0Great curassow (Craxrubra) 0 1 0 0 0 0 0 0

Nine-banded armadillo(Dasypus novemcinctus) 0 1 0 0 0 0 0 0Paca (Agouti paca) 1 1 0 0 0 0 0 0


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Red brocket deer(Mazama americana) 0 1 0 0 0 0 0 0Tayra (Eira barbara) 0 1 0 0 0 0 1 0

Table 4-3 Presence/absence of recorded species and there distribution across camera sites. Parque


All Stealth cams were set in the field up at least once during the phase. Due to various

malfunctions, cameras were in operation for variable amounts of time (7-30 trapping

days). Problems included lack of sensitivity, malfunctioning LCD screens, water seeping

inside the casing, incorrect number of pictures being taken, low battery light flashing and

technical difficulties with winding on of the film. Due to these difficuites, some sites

where either established with, or reduced to, only one camera unit.

Of the three films developed, one was water damaged, one was over-exposed and theother had no pictures of animals on it.

4.5 Discussion

Significant progress has been made with the camera trapping project this phase.

Although no jaguars were photographed, many of the jaguars prey species were

recorded such as the paca, the agouti, the great curassow, red brocket deer and the

tayra (Seymour 1989, Carrillo et al., 1994). Jaguar prints were also consistently recorded

on the nearby beach during weekly track surveys, thus it is clear that the target capture

species are present in the area.

Much has been learnt about site selection and camera operation this phase. At Site 1

(where 36 records were obtained), there was a fruiting tree, thus a possible reason for

the high number of records. Cameras placed here were functioning for 44 trapping

nights.

At Site 6, motion was detected during the night but the data could not be analysed dueto the flash function being switched off. In addition, the camera was mistakeinly set to

take six pictures (instead of two) and installed without an external memory card (a fourth

one was unavailable). Thus, the 16MB of internal memory was filled very quickly. Falling

leaves appeared to activate the motion detectors frequently, as well as small

unidentifiable lizards.


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In one instance it was found the batteries had lost charge after only four days in the field.

Cameras are only checked once every two weeks in order to minimize human impact on

the trapping sites locations, as such, it is vital to ensure cameras are set up correctly and

equipment is fully functioning.

The four digital cameras trialled this phase have given us the first consistent results

since the projects inception in November 2006. Next phase we shall continue to improve

the methods, building on the knowledge obtained this phase. We also intend to apply for

funding of additional digital cameras in order to have two digital cameras set per site and

bring our field trials in line with our study protocols, in anticipation of capturing our first

jaguar images.


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5 Large Mammal Monitoring Programme

5.1 Introduction

The impact of human activities such as tourism and hunting on Neotropical wildlife has

been studied in Costa Rica (Carrillo et al., 2000) and elsewhere in the region (e.g.Cuarn 2000, Naughton-Treves et al., 2003, Novaro et al., 2000, Redford 1992, Wright

et al., 2000). These studies have examined the relationship between these human

activities and patterns of animal abundance, distribution, and habitat use and their

results have determined that there is a negative effect on wildlife due to these human

associated activities and due to other variables such as land protection status. Scientific

evidence also shows that many mammal species are sensitive to certain pressures such

as change in land cover, habitat reduction, and poaching (e.g. Fonseca & Robinson

1990, Laurence 1990, Soul et al., 1992, Bodmer et al., 1997, Chiarello 1999, 2000,Laidlaw 2000).

There is believed to be an abundant and important wildlife population in the BCWR,

however little research has been undertaken in the area to quantify this. Some of the

species known to be present in the study area fill important ecological roles and include

many endangered species as legislated by Costa Rican law. such as jaguars (Panthera

onca) and other Neotropical wildcats, tapirs (Tapirus bairdii), white-lipped peccary

(Tayassu pecari), and Central American spider monkeys (Ateles geoffroyi).

The mammal monitoring programme began preliminary studies in phase 073 (11th July

19th September 2007) and began full transect surveys on 6th December 2007 (phase

074).

5.2 Aims

The general aim is to examine the species assemblage of arboreal and terrestrial

mammals (>0.5 kg in size) inhabiting the southern extent of the BCWR between CaoPalma and Cao Penitencia.

The projects specific objectives are to 1) estimate community composition and species

richness, 2) determine relative abundance of species and monitor its trends, 3) provide

other researchers with basic data on the arboreal and terrestrial mammal assemblage of


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Tortuguero, and 4) spread knowledge and appreciation of local wildlife diversity and

promote the social and environmental benefits of wildlife conservation efforts in the area.

5.3 Methodology

5.3.1 Study site

The transect is a 3,050 metre transect which runs east-west between Cao Penitencia

and Cao Palma. This survey site was chosen based on the suitability of the trail for

transect use as well as the trails proximity to EBCP.

The transect is marked with flagging tape, tied securely to natural landmarks, such as

trees, every 50-meter. The number of meters from the start of the transect is written on

each tape. The markers were recorded as waypoints in a GPS. Trees were also marked

with plain tape in areas that were difficult to navigate. Surveys are conducted from Cao

Penitencia (west) to Cao Palma (east) for logistical reasons.


General survey data recorded on survey was as follows:

Date (DD/MM/YYYY) Survey start and end time (24 hour clock)

Name of transect Weather conditions Team members initials (beginning with the staff member)

The categories of recording were as follows:

Visual Tracks Vocalizations Scat

Upon detection, the following data was recorded:

Encounter Time (24 hour clock) Last metre marker passed Record number Method of detection (i.e. visual, track, auditory) GPS location Species common name


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Species scientific name Track length and width, in millimetres (as well as initials of team member

measuring track) Whether or not a photograph of the track was taken (Y or N) Photo ID Initials of photographer Direction of travel and number of individuals identified Any other relevant information such as: activity, diet, elevation, stage of

development, sex, mixed species associations, vegetation

Surveyors remained on the transect line and any movement off the transect was limited

to a maximum of three metres to ensure data validity and minimize human impact.

Photographs were taken in the lower left corner of a setsquare with an ID card showing

the common name of the species and the record number. Photographs were then

numbered, and catalogued in the data folder specified for the programme.

5.4 Results

During phase 081 eight surveys were conducted with one week between surveys for a

total of 24.4 Km. The first survey took place on January 22nd 2008 and the last one on

March 10th 2008. The survey started first light, being the earliest start at 05.47am and the

latest start at 06.15am. The shortest survey took 4hrs 39min and the longest 9hrs 10min.

The total survey time was 58hrs 54min.

One preliminary survey was conducted on mile 15 on the Tortuguero National Park.

Barra del Colorado Wildlife Refuge Transect

ID Method

TotalRecordsVisual Vocalisation Visual/Vocalistion Tracks

Totals 19 4 4 34 61

Table 5-1 Number of records per ID method on Barra del Colorado Wildlife Refuge, Costa Rica.


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Preliminary study on mile 15 in Tortuguero National Park

ID Method

TotalRecordsVisual Vocalisation Visual/Vocalistion Tracks

Totals 2 1 0 5 8

Table 5-2 Number of individuals recorded per ID method, Tortuguero National Park, Costa Rica.

5.5 Discussion

The data collected in phase 081 indicates the presence of a variety of large mammal

species within the study area

Including the data collected during this phase 081, the database now comprises of 127

records for 16 large mammal species.

The continuing challenge of the programme has again proved to be the condition of the

transect. During the surveys conducted many other tracks were encountered that could

not be positively identified due to flooding and poor ground conditions and those

identified in the field are difficult to verify from photographs at a later date.

During this phase, in addition to surveying the original transect, there has been interest

from MINAE in establishing a new transect within Tortuguero National Park. The first

preliminary study indicated the presence of a variety of large mammals in the area. The

expansion of the research has potential to establish a long-term national partner for the

programme and a comparison of species diversity and density between TNP and

BCWR.


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6 Canal Bird Monitoring Programme

6.1 Introduction

Growing concerns about the status of birds in the rainforests of Central America has lead

to the establishment of long-term monitoring programmes and has in part lead to theinitiation of this study. The Estacin Biolgica Cao Palma (EBCP) Canal Bird

Monitoring Programme aims to quantify diversity and abundance of the species which

live and breed in the area of Caribbean Lowland Rainforest around EBCP, 7 km North of

Tortuguero National Park.

The nature of Costa Ricas bird life has meant that it has been a popular location to

study behaviour and diversity for many years. Much of this focus has been directed

towards migratory birds and the information on resident species is still in need ofconsiderable research.

The aquatic environment is of major importance to the tourism and ecology of the

tortuguero area. This habitat is being increasingly utilized and it is expected that this use

will, in time, have an impact on the avian population it supports.

The, EBCP Resident Bird Project monitoring survey began in July of 2005 and has been

developed into the current incarnation which is an ongoing project. Further collection of

data is important in order to establish reliable population trends for local bird species.

The GVI protocol is modified from the original protocol created by Steven Furino of

Waterloo University Canada. The modifications have been made to the protocol so that

data collectors with minimal field experience are able to collect high quality data suitable

for the study. This has involved reducing the number of species and study areas as well

as limiting the amount of technical data collected on species. In all other aspects the

research follows the original protocol.

6.2 Aims

This research programme is intended to accumulate data that will help researchers

examine long-term changes in specific bird population. The specific aims of the project

are 1) to identify study species use of the study areas, 2) monitor long-term changes in


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use of these areas, and 3) to aid in the collection of both resident and migratory avian

population data sets for wider public use.

6.3 Methodology

The study species were selecting based on two characteristics. Firstly, they occupy a

range of habitat within the aquatic environment, thus act as an indicator of disturbance.

Secondly, the study species are all relatively easily visualised and identified making

them ideal species for studies using low experience data collectors.

6.3.1 Study site

Within each area, sectors have been selected to aid with data collection and analysis.

These sectors have been selected to include a broad variation of habitats within thestudy areas.


The method of survey used in the study is an area search, which records all positively

identified study species seen or heard whilst searching a predetermined area. See

appendix A for exact locations of each sector.

For each survey the following general data was recorded:

Name of study site

Name of primary surveyor

Date of survey

Start time (using a 24 hour clock)

End time (using a 24 hour clock)


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The study species targeted for data collection were as follows:

Common name Scientific name

Agami heron Agamia agami

Amazon kingfisher Chloroceryle amazona

American pygmy kingfisher Chloroceryle aenea

Anhinga Anhinga anhinga

Bare-throated tiger-heron Tigrisoma mexicanum

Belted kingfisher Ceryle alcyon

Boat-billed heron Cochlearius cochlearius

Cattle egret Bubulcus ibis

Great blue heron Ardea herodias

Great rgret Casmerodius albus

Green heron Butorides s. virescensGreen ibis Mesembrinibis cayennensis

Green kingfisher Chloroceryle americana

Green-and-rufous kingfisher Chloroceryle inda

Gray-necked wood-rail Aramides cajanea

Least bittern Ixobrychus exilis

Limpkin Aramus guarauna

Little blue heron Egretta caerulea

Neotropical cormorant Phalacrocorax olivaceus

Northern jacana Jacana spinosa

Purple gallinule Porphyrula martinica

Reddish egret Egretta rufescens

Ringed kingfisher Ceryle torquata

Rufescent tiger-heron Tigrisoma lineatum

Snowy rgret Egretta thula

Sunbittern Eurypyga helias

Sungrebe Heliornis fulica

Tricoloured heron Egretta tricolour

White-throated crake Laterallus albigularis

Yellow-crowned night heron Nyctanassa violacea

Table 6-1 Canal bird monitoring program study species


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For each ea search only positively identified species were recorded. For each positive

record made the following data was collected:

Sector code at which species was observed

Number seen or heard (S: seen only, H: heard only, SH: seen and heard) Any comments e.g. breeding plumage or behaviour

6.4 Results

During phase 081 a total of 27 surveys were undertaken, nine on each of the study sites.

With the exception of one dusk Cao Palma survey, all were conducted at dawn.

Data collected on the aquatic trails entrance to Caos Chiquero and Harold has been

listed separately due to habitat differences. The waterway is much wider and contains agreater amount of grasses and floating vegetation in comparison to the Caos

themselves, so would be expected to yield different species. Twenty-three species were

recorded on the four study sites, see Figure 6-1 for a summary of the number of species

seen for each study area.

Figure 6-1 Total number of species on Cao Chiquero, Cao Harold and Cao Palma, Tortuguero,

Costa Rica.

0

5

10

15

20

25

Cao Chiquero Cao Harold Cao Palma


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The number of each study species recorded during surveys on Cao Chiquero, Cao

Harold, the aquatic trails entrance and Cao Palma are illustrated in figures 6-2, 6-3,6-4

and 6-5 respectively.

0

10

20

30

40

50

60

70

80

90

100

Bare-thr

oated

Tiger-H

eron

GreenH

eron

GreenKingfishe

r

Little

Blue

Hero

n

Sungreb

e

GreenIbis

Green-a

nd-rufou

sKingfishe

r

SnowyE

gret

Amazon

King

fishe

r

AmericanP

ygmy

King

fishe

r

Anhin

ga

Ringed

King

fishe

r

Grey-necked

Wood-R

ail

Rufes

centTig

er-he

ron

Species

P

ercentageofSurveysObserved

Figure 6-2 Study species recorded per survey on Cao Chiquero aquatic trail. Tortuguero National

Park, Costa Rica.

Fourteen different study species were identified on Cao Chiquero aquatic trail surveys.

The two most frequently observed species were the bare-throated tiger-heron and green

heron. The green kingfisher was recorded on 78% of surveys, and the little blue heron

and sungrebe on 67%.


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0

10

20

30

40

50

60

70

80

90

100

GreenH

eron

GreenKing

fisher

Green-and-rufousKing

fisher

Little

Blue

Heron

Bare-throated

Tige

r-Heron

AmericanPygmyKing

fisher

Boat-billedH

eron

Ringed

King

fisher

SnowyEgret

Sungrebe

Amazon

King

fisherAnhin

ga

Yellow-crowned

Nigh

t-Heron

AgamiH

eron

GreatEgret

GreenIbis

Grey-neckedW

ood-Rail

beltedking

fisher

NorthernJacana

Rufescent

Tiger-Heron

Sunbittern

Species

PercentageofSurveysObserved

Figure 6-3 Study species recorded per survey on Cao Harold aquatic trail. Tortuguero National

Park, Costa Rica.

Twenty-one different study species were identified on Cao Harold aquatic trail surveys.The most frequently observed species (identified on 100% of surveys), were the green

heron, green kingfisher, green-and-rufous kingfisher, and little blue heron. The bare-

throated tiger-heron was recorded on 89% of surveys and the American pygmy

kingfisher was seen on 67% of surveys


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0

10

20

30

40

50

60

70

80

90

100

Little

BlueHeron

Snowy

Egre

t

Green

Hero

n

Bare-

throated

Tiger-H

eron

Gree

nIbis

GreatE

gret

Anhin

ga

NorthernJ

acana

Belte

dKing

fishe

r

Amazon

King

fishe

r

Ringed

Kingfisher

Gree

n-and

-rufou

sKingfisher

Sungrebe

GreenKing

fishe

r

Yello

w-cro

wned

Night-Heron

Cattle

Egret

Gray

-necked

Wood

-Rail

Tricolored

Heron

Species

PercentageofSurveysObse

rve

Figure 6-4 Study species recorded per survey on the aquatic trails (AQT) entrance

Eighteen different study species were identified on the aquatic trails preceding the

Caos. The most commonly sighted species were the little blue heron and snowy egrets,

observed on 100% of surveys, along with the green heron, observed on 89% of surveysand the bare-throated tiger-heron and green ibis, recorded for 83% of surveys.


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0

10

20

30

40

50

60

70

80

90

100

Green

Kingfisher

Yellow-

crowned

Night-

Heron

Anhinga Green

Heron

Green Ibis Ringed

Kingfisher

American

Pygmy

Kingfisher

Amazon

Kingfisher

Bare-

throated

Tiger-

Heron

Grey-

necked

Wood-Rail

Great

Egret

Green-

and-rufous

Kingfisher

Species

PercentageofSurveysObser

ved

Figure 6-5 Study species recorded per survey on Cao Palma, Barra del Colorado Wildlife Refuge,

Costa Rica.

Twelve different study species were identified on Cao Palma during aquatic trail

surveys. The most frequently sighted species were the green kingfisher and yellow-

crowned night heron observed on 100% of surveys, followed by the anhinga and green

heron observed on 89% of surveys and the green ibis and ringed kingfisher seen on

78% of surveys.

6.5 Discussion

Of all the areas surveyed only Cao Harold and the aquatic trails had species exclusive

to them as the tricolored heron was only sighted on the AQTs and the agami heron and

the sunbittern were only sighted on Cao Harold. Furthermore, Cao Harold was thearea with the most uncommon/rare species (see Widdowson and Widdowson 2004) with

four, followed by Cao Chiquero and the AQTs with two and Cao Palma with one.

The data collected to date highlights the previous derth of informations pertaining to the

classification of certain species in the area One such species is the green ibis, which


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despite being classified in Widdowson and Widdowson (2004) as rare, was consistently

recorded on all study area over the phase. The occurrence of this species will be

reassessed in detail next phase to see whether the species abundance has changed

since the Widdowson list was created in 2004 and whether its status in the area should

be reclassified. For the following phases, it would be an interesting development to theprogramme to compare species abundancies recorded with those classifications

available for the area.

Further uses of the current data collection include investigating anthropogenic

disturbance of the area by using the current study species as indicators.

Determination of the extent to which ecological systems are experiencing anthropogenic

disturbance and change in structure and function is critical for the long-term conservation

of biotic diversity in the face of changing landscapes and land use (Canterbury et al.,

2000). This baseline study focused on counts of individual species within the specific

Caos of the National Park and reserve in order to give an indication of the key species

compositions found there.

It has been argued that continuous or frequent high intensity activities such as the use of

motorized power boats constantly throughout the day cause more disturbance than

continuous low intensity disturbance. It has also been said that in general birds appear

to habituate to continual noises so long as there is no large amplitude startling

component (Hocken et al., 1992; cited in Hill 1997). Another suggestion by Hill et al,

states that most water based recreation generates medium intensity, continuous or high

intensity infrequent disturbance. It is thus believed that medium disturbance may cause a

site to become unattractive to the more susceptible species whilst the latter could result

in displacement of the birds for short periods.

Data collected on individual study sites could be used over time to assess how certain

populations are changing, if at all, and how they use the specific habitat over the courseof a year.

The surveys undertaken during phase 081 have assisted in increasing the overall data

set. Whilst the findings from this phase do not highlight any unexpected or unusual

patterns in the local bird populations they have helped identify areas where continued


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improvement to the methodology is required in order to gain the most useful and

accurate data.


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7 Incidental Species Study

7.1 Introduction

The EBCP Incidental Species Study was initiated during phase 071 (January March

2007). The project has gone through various changes over the phases in order tosimplify the data collection methods and ensure each species is positively identified and

accurately recorded. By keeping a daily record of the occurrence of species found

around base, we can determine which species are seen most frequently and determine if

there any changes in the frequency of sightings of certain species over time. This is

important to determine if the presence of people around base for the majority of the year

is having an effect on the wildlife present.

7.2 Aims

The aim of the study is to maintain a formal, accurate record of the daily occurrences of

birds, mammals, reptiles and amphibians sighted within the property boundaries of the

station.

7.3 Methodology


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Phase 081 Report Final Version

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