DEVELOPING A MANGROVE MONITORING PROGRAM FOR THESAN JUAN BAY ESTUARY

Christopher Nytch, Osé Pauléus, Chao WangOctober 14, 2013

Mangroves in Puerto Ricoestuario.org

Martinuzzi et al. 2009

Importance of mangroves

Habitat for fish, shrimp, crabs and marine invertebrates

Foraging, roosting nesting sites for birds and reptiles

Ecosystem services Timber for homes & fuel Food Protection from storm impacts, coastal

erosion Spiritual and recreational experiences

www.nzdl.org

www.puerto-rico-tourism.com

Changes in mangrove cover in PR

Extent of the mangrove cover in Puerto Rico, including the four historical periods of change (between parenthesis). Original estimates for the years 1968, 1971, 1972, and 1974 (white diamonds) where averaged and combined into one single value for 1971. Data for other years is showed in black squares. Source: Martinuzzi et al. 2009.

Mangroves currently cover 8,700 ha (1%) of Puerto Rico

Maps showing 1) mangroves within the San Juan Metropolitan Area (i.e., urban sites); in this area, Caño Martín Peña (site ‘‘a’’ in the lower image) increased in mangrove forest cover between 1977 and 2002 due to restoration efforts, while Rio Puerto Nuevo (site ‘‘b’’) decreased. Inset 2) shows an urban–rural site, which decreased in forest cover, and inset 3) correspond to a rural site, which increased. Source: Martinuzzi et al. 2009.

Changes in mangrove cover in PR

Forces of mangrove loss and gainMartinuzzi et al. 2009

estuario.org

80grados.net

Mangrove Protection

1972 “organic” law creates DRNA and protects mangroves anywhere they occur in PR

Twenty-five additional state and nine federal laws and regulations protect mangroves (Torres Rodríguez 1994)

Since the 1970s, overall mangroves have expanded throughout coastal areas, inside and outside reserves, in rural areas, and in some developed landscapes (Martinuzzi et al. 2009)

Active restoration in some sites Caño Martín Peña

Ongoing Threats

The legal approach has not prevented negative effects of human decisions and activities related to mangroves

While the area of mangroves has increased over the last decades for the entire island, it has decreased in certain sites Threats (Lugo 1988, Martinuzzi et al. 2009, Miller and Lugo 2009)

Coastal development Fragmentation from roads Pollution, sediment and

nutrient runoff Uncontrolled recreation Natural disturbance, (e.g.,

hurricanes) Projected rises in sea level

PRCCC 2013

Research Problem

We know: How human activities and land use change

patterns have affected mangroves over the past 200 years

What’s lacking: Detailed monitoring of mangrove habitats and

current patterns of change in response to various threat factors and conservation activities In order to improve future management and zoning

regulations

Research Goal

Develop a multi-scale monitoring program in the San Juan Bay Estuary (SJBE), as a pilot project to track fine-scale changes in the spatial extent and structure of mangrove habitats over time in response to natural and human-induced processes. Similar to the water quality monitoring

project already underway

Objectives

1) Map the current distribution and extent of mangroves (per type) in the SJBE;

2) Document fine-scale changes in SJBE mangrove distribution, extent and forest structure (mangrove type) from 2001-present;

3) Calculate the rate of increase or decrease since 2001 in mangrove patches within the SJBE;

4) Assess mangrove changes in relation to urban development, access, and species type;

5) Collaborate with the SJBE to develop a protocol for regular monitoring of mangrove at multiple scales using remote sensing techniques and citizen science methods;

6) Establish a series of monitoring points throughout the SJBE to carry out long-term observational studies of mangrove dynamics;

7) Implement the monitoring program with the aid of SJBE Program citizen scientists to collect initial data;

8) Evaluate the results and effectiveness of the monitoring program.

Hypotheses

Based on mapping and habitat analysis from 2001-2013: 1) The rate of change of mangrove cover has remained

constant.

2) Changes in mangrove cover are dependent on location. 2a. Proximity to urban areas and roads is positively correlated

with mangrove reduction.

3) Changes in mangrove cover affect species differentially. 3a. Mangrove forest structure is changing with some species

gaining and others losing.

Study Site: San Juan Bay Estuary

160 bird species 124 fish species 19 species of reptiles/

amphibians 300 species of wetland

plants Mangroves

1/3 of all remaining mangroves in PR

6 sites Piñones State Forest Suarez Canal Caño Martín Peña San Juan Bay San Jose Lagoon Condado Lagoon

3,400 acres / 1,376 ha 80% urbanized >8,300 persons/mi2

estuario.org

Methodology I – baseline analysis

To be carried out by the research team Mapping of current mangrove land cover and changes from

2001-2013 Quickbird satellite imagery

Spatial analysis (ArcGIS) to interpret mangrove species distribution and extent

Evaluation of image interpretation from field visits Analysis of changes in mangrove cover at all six sites

Location Urban proximity Roads proximity

Logistic regression

Species patterns Relative abundance of black vs. red vs. white vs. button mangroves

ANOVA

Methodology II – monitoring program

Together with the SJBE Program: Discuss monitoring priorities and objectives:

Assessment examples Rise in sea level

1) Loss of mangroves due to erosion of seaward margin 2) Relocation and migration of mangroves inland 3) Change in mangrove forest structure, such as landward

replacement of black by red mangrove Water quality & pollution Excessive recreation Fragmentation

Develop monitoring criteria Develop monitoring protocol

Remote sensing techniques Field data collection Decide on monitoring frequency

Example: 2x / year– wet and dry season

Methodology II (cont.)

Together with the SJBE Program: Establish long-term monitoring points Organize local community volunteers and materials Implement monitoring and collect initial data (1-

year) in collaboration with SJBE scientists SJBE program citizen scientists

Evaluate monitoring program success and recommendations

Report results Official report Community forum Education materials

Potential benefits

Provide a systematic procedure for collecting detailed data about patterns and processes of mangrove change through time.

Better inform natural resource managers involved in conservation planning/design and restoration.

Generate public awareness about the importance of mangroves and their risk factors.

Build collaborative management relationships among residents, the SJBE Program, and the DRNA.

Test-drive a pilot monitoring project that could be expanded island-wide.

Activities & Timeline

Month 1 Month 24

Month 6

Month 12 Month 18

Evaluate program & final report

Implement monitoring & collect initial data

Organize local community volunteers & monitoring materials

Discuss & Develop monitoring criteria

Develop monitoring protocol & Establish monitoring points

Mangrove analysis & mapping

Budget

References

Lugo, A. 1988. Estimating reductions in the diversity of tropical forest species. Pp. 58-70 in E.O. Wilson (Ed.), Biodiversity. National Academy Press, Washington, D.C.

Martinuzzi, S., W.A. Gould, A.E. Lugo, and E. Medina. 2009. Conversion and recovery of Puerto Rican mangroves: 200 years of change. Forest Ecology and Management. 257:75-84.

Miller, G.L. and A.E. Lugo. 2009. Guide to the ecological systems of Puerto Rico. Gen. Tech. Rep. IITF-GTR-35. San Juan, PR: U.S. Department of Agriculture, Forest Service, International Institute of Tropical Forestry. 437 pp.

Torres Rodríguez, M., 1994. Plan de manejo para los manglares de Puerto Rico. Estado Libre Asociado de Puerto Rico. Departamento de Recursos Naturales y Ambientales, San Juan, PR.