Many mysteries still surround the world of marine biodiversity. Microbes

compose a huge portion of the organisms in the marine environment, but

little is known about their behavior, abundance, and diversity. This study

focuses on the diversity and distribution of Vibrio species. Many known

and unknown species of Vibrio bacteria exist in the ocean, and some,

such as V. cholerae, are known to be pathogenic. Vibrio live not only in

sea water, but also on floating biotic and abiotic substrates. In order to

better understand the qualities of these bacteria samples of plastic, sea

water, and Sargassum were taken from different stations across the

latitudinal gradient of the Sargasso Sea. Samples were measured for

morphotype diversity. After isolating specific colonies, DNA from specific

samples was extracted and sequenced. We hypothesized that differences

in morphotype diversity would occur among the three mediums. Of the

bacteria colonies studied, morphological and genetic differences were

found in the bacteria among the different substrates as well as between

the different locations along the latitudinal gradient. While the data

collected indicates some morphotypes of Vibrio are substrate and

location specific, further research is needed to fully assess the

implications of this study. Many variables need to be considered when

making predictions about Vibrio substrate and location specificity.

Abstract

Methods

Results & Discussion

Conclusions

In the Sargasso Sea, a majority of the morphtypes are

rare occurring with only a few common morphotypes.

Sea water has the greatest diversity of morphotypes,

followed by Sargassum, and then by plastic debris.

Majority of the Vibrio morphotypes are substrate

specific; about 10% of all morphotypes are found on all

three substrates.

A correlation appears to exist between latitude and the

morphotype richness on plastic debris and Sargassum.

However, this was not observed for sea water.

A clear and gradual change in morphotype composition

across the latitudinal gradient was observed.

There are genetic differences of the Vibrio colonies

across different samples

We recommend further research on Vibrio and the

microbial community in the open ocean

Policy Implications

This study has provided a preliminary understanding of

Vibrio biodiversity in open-ocean ecosystems. As abiotic

factors such as anthropogenic debris pollution and sea

surface temperature continue to change, the potential

negative effects Vibrio can have on human health and

commercial marine species make them important

organisms to study and understand. Furthering our

knowledge on the diversity of Vibrio and other relevant

microbes in the Sargasso Sea can, in the future, raise

awareness of the growing need for better education

and management of our oceans and seas.

Acknowledgements

The funding to support this work was provided by NSF-

TUES grant DUE-1043468. We would like to thank Sea

Education Association (SEA) for making this research

project possible and to Dr. Amy NS Siuda, Dr. Erik R

Zettler, Dr. Linda Amaral-Zettler, and Annie Scofield,

whose advice, feedback and comments much improved

our research and paper.

Collected plastic debris, Sargassum, and sea water samples daily from noon

neuston station at different latitudes in the Sargasso Sea

Stamped samples on CHROMagar™ Vibrio to select for Vibrio species

After 48 hours of growth on CHROMagar™, the morphoptypes were identified

using a morphotype description key

Vibrio colonies of interest (49 colonies) were transferred to Tryptone Sea

Water plates for isolated growth

DNA was extracted with Lyse and Go reagent and then amplified by PCR and

sequenced for the 16S rRNA gene

Sequenced DNA was aligned and trimmed to compare with known Vibrio

species and analyzed with BLAST

Allison Adams 1,2, Cheng Cheng1,3 , Ben Ong1,4 , Yip Ye1,5

1Sea Education Association, Woods Hole, MA, 2Syracuse University, Syracuse, NY, 3Knox College,

Galesburg, IL, 4Rice University, Houston, TX, 5Macalester College, Saint Paul, MN

A Study of the Biodiversity of Vibrio Bacteria in the Sargasso Sea

Figure 3. Number of morphotypes of Vibrio bacterial colonies isolated from plastic, Sargassum, and seawater in the Sargasso Sea across the latitudinal gradient ranging from 18.67° to 37.44°. An overall decreasing trend in morphotype richness in plastic and Sargassum was observed, which could be associated with the falling sea surface temperature. With regards to seawater, no observable trends could be identified.

Figure 1. Rank-abundance curve for the 53 bacterial colony morphotypes observed from samples collected at neuston tow stations in the Sargasso Sea stations between St. Croix, USVI and Woods Hole, MA. This graph shows that a majority of the morphotypes were rare with a few commonly occurring morphotypes.

Figure 2. Morphotype accumulation curves of Vibrio bacterial colonies found on plastic, Sargassum and sea water. It suggests that seawater has the greatest diversity of morphotypes, followed by Sargassum and then by plastic debris. Also, there is no sign of plateauing for the seawater accumulation curve.

Figure 4. Distribution of substrate specificity of the Vibrio morphotypes found on plastic, Sargassum, and seawater in the Sargasso Sea. A majority of the morphotypes were substrate specific with approximately 10% being completely non-specific

Figure 5. Changes in the diversity and abundance of morphotypes that occurred at least 4 times across the latitudinal gradient. There is an obvious change in morphotype composition.

DNA Analysis

Figure 7. A DNA Alignment with MEGA software of 5 consensus sequence from Vibrio samples compared against 4 known Vibrio species. Samples are Vibrio bacteria and are genetically different.

C-241 Cruise Track and location of all Neuston Tow Stations

Vibrio bacteria growing on CHROMagar™ Vibrio after 48 hours

Abstract

Hydroids on pelagic Sargassum natans and S. fluitans were studied in samples collected between St. Croix, USVI and Woods Hole, MA during May and June 2012. The study examined the hydroids present on 125 S. fluitans leaves and 100 S. natans leaves. A total of seven hydroid species were observed in these samples, one exclusive to S. natans and four exclusive to S. fluitans. Aglaophenia latecari-nata comprised 65.47% of all hydroids collected from S. fluitans leaves, and Clytia noliformis comprised 60.46% of hydroids collected from S. natans leaves. The S. fluitans hydroid community was more diverse than the S. natans hydroid community, with statistical significance at 95% confidence. Two species, A. latecarinata, and Plumularia margaretta, were present at all latitudes. C. noliformis, Plumularia seta-ceoides, Dynamena quadridentata, Sertularia meyeri, and Clytia johnstoni were only observed in particular latitudinal regions. The relative abundance of A. latecarinata decreased as latitude increased. Higher relative abundances of P. margaretta were observed in samples that were collected further north. Linear regressions did not indicate strong correlations between Shannon diversity index and SST, salinity, chlo-rophyll-a fluorescence, or wet mass of Sargassum collected during the neuston tow.

Background

-Hydroids are colonial, polymorphic, epifaunal, organisms in the phylum Cnidaria

-Important food web foundation

-Variation of hydroid communities on S. fluitans vs S. natans (Calder 1995, Thomas 2005)

-Variation of hydroid communities within regions of the North Atlantic (Stoner and Greening 1984, Keller 1987)

-Few recent studies – most done in the 1970s and 1980s

Methods

-North Atlantic cruise transect extended from St. Croix, USVI to Woods Hole, MA

-Sargassum (hydroid substrate) were collected twice daily using neuston tow

-Five leaves each of Sargassum natans and Sargassum fluitans were randomly selected if present from each neus-

ton tow.

-Hydroids were counted and identified to species

-Genetic identification was conducted to confirm morphological identification of hydroids by amplification and se-

quencing of the 18S ribosomal rRNA gene

Results

Figure 4: Hydroid species composition over 5° sections of latitude (A) 16º-20º N latitude (B) 21 º-25º N latitude (C) 26º-

30º N latitude, and (D) 31º-32º N latitude

Aglaophenia latecarinata

Clytia noliformis

Plumularia margaretta

Hydroid Diversity in the Sargasso Sea

Emily Allen 1,2, Grace Hutton 1,3, and Elissa Walter 1,4 1SEA Education Association, Woods Hole, MA 2St John’s University, Queens, NY

3Northeastern University, Boston, MA 4Carleton College, Northfield, MN

Figure 1: Hydroid community composition on S. fluitans and S. natans

Figure 2: Biodiversity of hydroid community present on

S. fluitans (n=25) and S. natans (n=20) in the North At-

lantic Ocean (mean +/- 95% confidence intervals)

Hydroid Anatomy

Figure 3: Phylogenetic placement of Aglaophenia cf. latecarinata from the Sargasso Sea. The evolutionary history was inferred neighbor joining method in MEGA. Tree is drawn to scale all positions containing gaps and missing data were eliminated.

Conclusion

-Differences is leaf size could account for hydroid species composition differences in S. fluitans vs.

S. natans.

-Different relative abundances of S. fluitans and S. natans at different latitudes could account for hydroid

species composition differences at different latitudes.

-Fewer total species of hydroids were identified as compared to previous studies. The question then arises

of whether the discrepancy in results is due to sample size or a decrease in hydroid species in the Sargasso

Sea.

-The hydroid species composition and

relative abundance differed between S.

fluitans and S. natans.

-Hydroid community compositions varied

at different latitudes; as the latitude

increased, different hydroid species were

observed and the dominant hydroid

species changed.

-One sample of genomic data was

generated in the genetic analysis. The

sample had been identified morphologi-

cally as A. latecarinata. No 18S rRNA

gene sequence for A. latecarinata was

available in GenBank, but there was a

16S ribosomal rRNA sequence.

Policy Implications

When forming marine conservation strategies it is important to understand how community composition

varies in different locations. A successful strategy for one area may not be successful in another area.

Hydroids are a fundamental part of the food web in the Sargasso Sea and should be considered in any

conservation plan. Our study shows that hydroid communities differ with respect to latitude and Sargassum

species, which is valuable knowledge for policy makers focusing on conservation in the Sargasso Sea.

Acknowledgments

Funding to support this work was provided by NSF-TUES grant DUE-1043468

Special thanks also to Dr. Amy Siuda, Dr. Erik R Zettler, Dr. Linda Amaral-Zettler, the crew of the SSV

Corwith Cramer, and SEA class C-241

Results (continued)

Distribu(on  of  pelagic  Sargassum  in  the  Sargasso  Sea  Janet  Bering1,2  and  Alex  Binford-­‐Walsh1,3  

1  –  Sea  Educa>on  Associa>on,  Woods  Hole,  MA  2  –  Middlebury  College,  Middlebury,  VT,  3  –  Colorado  College,  Colorado  Springs,  CO  

Acknowledgements:  The  authors  would  like  to  thank  the  faculty,  students  and  crew  of  the  SSV  Corwith  Cramer  as  well  as  Amy  Suida,  Erik  ZeLler,  Linda  Amaral-­‐ZeLler  and  Annie  Scofield.  Funding  to  support  this  work  was  provided  by  NSF-­‐TUES  grant  DUE-­‐1043468.  

Works  Cited:  Gower,  J.F.R.  and  S.A.  King.  2011.  Distribu>on  of  floa>ng  Sargassum  in  the  Gulf  of  Mexico  and  the  Atlan>c  Ocean  mapped  using  MERIS.  Interna>onal  Journal  of  Remote  Sensing.  32:  1917-­‐1929.  Many  figures  created  using  Ocean  Data  View.  Schlitzer,  R.,  Ocean  Data  View,  hLp://odv.awi.de,  2012.    

Background  •   Sargassum  supports  a  large  community  of  other  species,  including  several  endemic  species  •   Represents  most  of  the  primary  produc>vity  in  the  top  meter  of  the  water  column  •   Broad  geographic  range:  Gulf  of  Mexico,  Caribbean  Sea,  Gulf  Stream,  Sargasso  Sea  

Satellite  Data  • Largest  blooms  seen  in  the  Gulf  of  Mexico  in  April  and  May,  and  in  the  Gulf  Stream  between  June  and  September  • Proposed  circula>on  paLern:  blooms  in  the  Gulf  of  Mexico  in  April,  transported  around  Florida  in  May  and  June,  re-­‐groups  in  the  Gulf  Stream  in  the  summer,  from  there  is  dispersed  throughout  the  Sargasso  Sea  (Gower  and  King  2011)  • Ques>ons  remain:  seasonality?  Repopula>on  of  Gulf  of  Mexico?  Differences  between  the  species?  

Methods  • Mass  of  Sargassum  divided  by  species  collected  in  Neuston  tows  (300  micrometer  mesh)  on  SEA  Cruises  C237  –  C240  from  October  2011  to  June  2012  (Figure  1)  • Rela>ve  age  of  3  clumps  collected  in  tows  (Figure  2)  • Hourly  visual  observa>ons  of  clump  and  windrow  presence  (Figure  3)  

4. Discussion

A significant feature of figure 2 is the temporal continuity of the signal that weinterpret as due to Sargassum. The movement of Sargassum over many months isconsistent from year to year, and can be explained by prevailing surface currents andwinds. The data clearly indicate strong growth early in the year in the Gulf ofMexico,with Sargassum advected by the Loop Current andGulf Stream into the Atlantic eachyear in July and August. Data for the years 2003 to 2007 suggest that the Gulf ofMexico is the dominant source of Sargassum. Passive surface floats (ISDM2008) takeabout a month to travel from the northeast Gulf of Mexico near 27!N, 85!W to theeast of Cape Hatteras at 36!N, 75!W. This is a short enough time to be consistent withour interpretation of the movement of Sargassum.

The average spatial pattern of the annual cycle is shown schematically in figure 5. Ineach year, Sargassum is first detected in a small area of the northwest Gulf of MexicoinMarch, which expands and spreads eastwards. In July Sargassum is present in boththe Gulf and the Atlantic off Cape Hatteras, spread eastwards to about 45!W by theGulf Stream in September. The northeast trade winds then move the Sargassum southand west over autumn and winter (October to February). Counts were very low in theAtlantic for the months of March, April and May in 2003 to 2007, although in 2008significant Sargassum remained in the area northeast of the Bahamas in this season.

Our observations are consistent with earlier ship-based surveys. Parr (1939)reported on 194 surface net tows designed to collect Sargassum in the Sargasso Sea,Caribbean andGulf ofMexico, in 1933, 1934 and 1935. Of these, 160 were in January,February or March, and the remaining 34 in April, July and August. Given the

Figure 5. Simplified outline diagram showing the average extent of Sargassum in March,May, July, September, November and February, based on MERIS count distributions bymonth as shown in figure 2. Only in 2008 does MERIS detect significant Sargassum in theAtlantic between March and June (dashed outlines).

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Conclusions  • We  see  higher  abundances  of  Sargassum  in  the  fall  in  North  Sargasso  Sea  and  in  the  winter  in  the  South  Sargasso  Sea  • Large  abundances  of  Sargassum  in  the  north  in  the  fall  could  be  seasonal  blooms  based  on  loca>on  of  nutrients  • Currents  and  wind  paLerns  rather  than  overall  growth  rate  leads  to  forma>on  of  windrows  • Sargassum  fluitans  is  more  abundant  at  lower  la>tudes  and  in  the  Caribbean  than  S.  natans    • Sargassum  is  present  in  clumps  even  when  not  in  large  windrows.  • Further  research:  effect  of  climate  change,  popula>on  gene>cs  Conserva(on  Implica(ons  • preserving  full  distribu>on  of  Sargassum,  not  just  seasonal  blooms  • Need  to  preseve  both  species,  because  they  have  different  ranges  

S.  fluitans  

S.  natans  

Maps  

General  Locale  Map   Map  of  cruise  track  C241,  Spring  2012  

Figure  5.  Wet  mass  of  Sargassum  collected  in  Neuston  tows  (a)  in  Fall  2011  on  cruise  C237  and  (b)  in  Spring  2012  on  cruise  C241.  Color  gradient  represents  mass  in  grams.    

Figure  6.  Propor>on  of  the  wet  mass  of  Sargassum  that  was  S.  natans  collected  in  Neuston  tows  in  (a)  Fall  2011  on  cruise  C237  and  (b)  in  Spring  2012  on  cruise  C241.  Dark  blue  areas  represent  high  propor>ons  of  S.  natans,  while  lightly  colored  or  white  gaps  in  the  cruise  track  represent  S.  fluitans.    

Fall   Spring  

Figure  7.  Number  of  Sargassum  clumps  seen  during  hourly  six  minute  observa>ons  in  (a)  Fall  2011  on  cruise  C237  and  (b)  in  Spring  2012  on  cruise  C241.  

Figure  8.  Number  of  windrows  seen  during  hourly  six  minute  observa>onsin  (a)  Fall  2011  on  cruise  C237  and  (b)  in  Spring  2012  on  cruise  C241.  

Fall   Spring  

Fall   Spring  

Fall   Spring  

Figure  4.  The  average  mass  of  (a)  S.  natans  and  (b)  S.  fluitans  collected  in  Neuston  net  tows  from  cruises  C237-­‐C241  between  October  2011  and  June  2012  in  different  regions  in  the  fall,  winter  and  spring.  Regions  are  defined  by  SEA  general  locale  conven>ons  as  seen  in  Maps.  Asterisks  indicate  regions  where  no  data  were  collected  for  that  season.  Error  bars  indicate  standard  error  about  the  mean.    An  error  bar  of  zero  indicates  that  only  one  sample  was  available  for  that  season.  The  data  labels  indicate  average  wet  mass  in  grams.  The  variance  in  S.  natans  was  not  sta>s>cally  significant  across  seasons  (n=18,  F=1.4,  p=0.29)  or  in  different  loca>ons  (n=18,  F=1.16,  p=0.38).  The  variance  in  S.  fluitans  was  not  sta>s>cally  significant  across  seasons  (n=18,  F=1.24,  p=0.32)  or  loca>ons  (n=18,  F=0.99,  p=0.47).  In  the  South  Sargasso  Sea,  the  abundance  of  S.  natans  was  rela>vely  constant  throughout  the  year.  Sargassum  natans  had  a  rela>vely  low  abundance  in  the  Caribbean  Sea.  The  abundance  of  S.  fluitans  remains  rela>vely  constant  throughout  the  year  in  the  Caribbean  Sea  and  in  the  South  Sargass.  Both  species  are  more  abundant  in  the  North  Sargasso  Sea  and  in  the  Gulf  Stream  in  the  fall  than  at  any  other  >me  of  year  or  in  any  other  loca>on.  

Map  of  cruise  track  C237,    Fall  2011  

Figure  1.  Neuston  net   Figure  2.  Clump  processing   Figure  3.  Visual  observaGon  

Results  

Figure  9.  The  average  extent  of  Sargassum  in  March,  May,  July,  September,  November  and  February,  based  on  satellite  imagery.  Black  arrows  represent  proposed  Sargassum  circula>on  (From  Gower  and  King  2011).    

Abstract  Sargassum  fluitans  and    Sargassum  natans  are  two  species  of  pelagic  algae  found  in  the  Sargasso  Sea.    Although  Sargassum  is  abundant  over  a  large  geographic  range,  liLle  is  known  about  its  distribu>on.  A  recent  paper  used  satellite  data  to  map  the  distribu>on  and  movement  of  Sargassum  (Gower  and  King  2011).  To  examine  Sargassum  ecology  and  to  evaluate  the  Gower  and  King  hypothesis,  data  collected  on  SEA  research  cruises  from  October  2011  to  June  was  examined.  Abundance  was  evaluated  by  measuring  the  mass  of  both  Sargassum  spp.  collected  in  Neuston  tows  conducted  twice  daily  and  through  hourly  visual  observa>on  of  windrows  and  clumps.    Sargassum  was  more  abundant  in  the  fall  in  the  North  Sargasso  Sea  and  the  Gulf  Stream  and  more  abundant  in  the  spring  in  the  South  Sargasso  Sea.  Sargassum  natans  was  more  abundant  at  higher  la>tudes  while  S.  fluitans  was  more  abundant  at  lower  la>tudes.      Although  the  sampling  range  did  not  cover  en>re  range  of  Sargassum,  the  results  were  in  agreement  with  the  Gower  and  King  paper.    While  Sargassum  was  found  to  have  some  seasonal  and  species  varia>on  in  abundance,  it  was  also  present  throughout  the  year  over  its  en>re  range  in  low  abundance.  

Results/Discussion Continued:

Population Genetics and Dynamics of Caribbean Spiny Lobster (Panulirus argus) Phyllosoma in the Sargasso Sea

Jody Daniel1,2, Jeremy Pivor1,31 Sea Education Association, 2 St. George’s University, St. Georges, Grenada, 3 Washington University in St. Louis, St. Louis, Missouri

Methods:•Phyllosoma were collected aboard the SSV Corwith Cramer research cruise between May 14th – June 17th 2012 from St. Croix to Woods Hole, Massachusetts via Bermuda.

•A neuston net and meter net (~10m below the surface) were deployed at 0000 daily along a 1 nautical mile transect at 2 knots (Fig. 1).

•Temperature, salinity, and chlorophyll afluorescence were measured along the ship’s path.

•Phyllosoma were classified to species and life stage using the body length (BL), cephalic shield length (CL), cephalic shield width (CW), thorax width (TW), andmicroscopy (Fig. 2).

•Neural and muscle tissue were used for DNAextraction and sequenced using the hypervariable domain of the mitochondrial DNA control region (HV-CRd1) with the primers CRL-F and CRL-R.

•23 samples were sent for DNA sequencing,and consensus reeds with an 85% identity to P. argus were used for analysis.

Fig. 2: Diagram showing measurements of Panulirus argus phyllosoma. (Goldstein et al. 2008)

Fig. 1: Neuston net deployment

SSV Corwith Cramer

Abstract:The Caribbean Spiny Lobster, Panulrius argus, is widely distributed across the Atlantic Ocean and itsfishery is ranked as the second most economically important in the Central Atlantic region. Stocks havebeen decreasing since the early 21st century. Management of the fishery has been difficult given the wideuncertainty regarding Spiny Lobster population dynamics. The long-range dispersal of the planktoniclarvae, called phyllosoma, makes it difficult to determine P. argus population structuring. Uncertaintyregarding local or distant recruitment of lobster stocks has made it difficult to create managementstrategies. The Sargasso Sea may serve as critical habitat for phyllosoma in acting as a corridor betweenstocks in the Gulf of Mexico, Florida, South America, and the Caribbean. In our study we have explored theinfluence of selected environmental parameters on phyllosoma distribution, as well as genetic and life stagestructuring in the Sargasso Sea in order to understand Panulirus argus population dynamics. We found nosignificance between phyllosoma abundance and temperature, salinity, or chlorophyll a concentration.Examination of historical records from Sea Education Association 1979-2012 cruises and our data in theSargasso Sea revealed a narrow temperature range in which phyllosoma were found (18.0o-28.3oC).Additionally, the temporal variations of phyllosoma abundance from Sea Education Association archiveddata from 1985-2012 in the North and South Sargasso Sea was relatively variable. Life stage structuringand genetic analysis of the phyllosoma collected, and previously sequenced adults from Diniz et. al. 2005,(357bp) supports the Pan-Caribbean Panmictic theory of distant recruitment. This suggests the need forregional management of the Caribbean Spiny Lobster.

Results/Discussion:

V18%

VI14%

VII29%

VIII25%

IX7%

X3%

Puerulus 4%

Fig. 3: Proportion of phyllosoma P. arguslife stages collected from St. Croix to Bermuda (n=27). Figure shows that life stages 8 and 7 constituted 54% of the P. argus collected, while no phyllosoma below life stage 5 were found

0

1

2

3

4

South North

Average # of Phyllo

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Collected

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1985‐19911992‐19981999‐20052006‐2012

y = 1.6286x ‐ 30.666R² = 0.0617p=0.1447

0

5

10

15

20

25

30

35

40

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Fig. 4: Average phyllosoma collected at each station between 1985-2012 in the South and North Sargasso Sea. Figure shows that the average abundance of phyllosoma collected is highly variable.

Fig. 5: Number of phyllosoma collected along Sea Education Association cruises from 2010-2012 (diamond) in the Sargasso Sea, including P. argus from cruise C241 (St. Croix to Bermuda) (square), with respect to sea surface temperature. Figure shows that phyllosoma abundance from C241 was observed to peak at 26.3oC and ranged from 24.2-26.4 oC

Fig. 6: Number of phyllosoma collected along SEA Education Association cruises from 1979-2012 in the Sargasso Sea with respect to sea surface temperature. Figure shows an observed ecological trend of greater phyllosoma abundance within a narrow temperature range of 18.0o-28.3oC.

Fig. 8: Life stages and genetic lineages of phyllosoma collected at each station across latitude from St. Croix to Bermuda during cruise C241. Highest life stages (9 and 10) were collected in northern latitudes. Life stage structuring was relatively heterogeneous across the transect. Station 012 contained the greatest heterogeneity in life stages. The figure shows that 75% were associated with evolutionary linage 1 and 25% were related to evolutionary linage 2. Station 012 contained phyllosoma of both lineages 1 and 2. There were no genetic patterns found with increasing latitude.

Conclusions:•Distribution of phyllosoma may be limited or impacted by sea surface temperature.•Further analysis on the possible impact of salinity and chlorophyll a concentration are required.•The temporal variations of phyllosoma abundance in the North and South Sargasso Sea may be related to adult population dynamics or distant spawning events during the reproductive season, but do not match the decreasing trend of adult stocks.•Genetic analysis and life stage structuring from our study supports the Pan-Caribbean Panmictic theory versus the Closed System theory.

Policy Implications:Given the observed mixing of populations, and therefore support for the distant recruitment theory, a regional fisheries management approach may be a feasible option for the Caribbean Spiny Lobster fishery. Further research though is needed to determine stock origins in order to enable more specific regional collaboration.

Fig. 7: Maximum Likelihood tree describing evolutionary relationships among 32 P. argus haplotypes from (24 adults) Diniz et al 2005 and 8 phyllosoma (1 from C230A and 7 from C241) (highlighted), resolved on the basis of (357bp) HV-CRd1. Bootstrap values based on 1000 replicates representing all nodes. The tree shows that phyllosoma collected had similar genetic structuring to previously sequenced adults. No phyllosoma were genetically similar to the Brazil population. The figure also shows indiscrete population structuring of phyllosoma within lineages 1 and 2.

Lineage 1

Lineage 2

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Acknowledgments:The authors are thankful to the Sea Education Association for providing the transportation and equipment needed to carry out this research. We are also grateful to Dr. Amy Suida, Dr. Erik Zettler, Dr. Linda Amaral-Zettler and Ms. Annie Scoffield for their insightful advice and assistance during the study and data analysis period. We are also thankful to the crew of the SSV Corwith Cramer and the C-241 class for their support during our project (especially the cool, calm, collected C watch). Lastly, we are grateful to Mr. Greg Boyd and the Bermuda Aquarium, Natural History Museum and Zoo for providing us with neural tissue samples from adult lobsters for genetic analysis.

References:•Diniz, F.M., N. Maclean, M. Ogawa, I.H.A. Cintra, AND P. Bentzen. 2005. The hypervariable domain of the mitochondrial control region in Atlantic spiny lobsters and its potential as a marker for investigating phylogeographic structuring. Mar. Biotech. 7: 462-473, doi: 10.1007/s10126-004-4062-5.•Goldstein, J. S., H. Matsuda, T. Takenouchi, AND M. J. Butler IV. 2008. The complete development of larval Caribbean spiny lobster Panulirus argus in culture. J. Crustacean Biol. 28: 306-327.•Lyons, W. G. 1980. Possible sources of Florida’s spiny lobster population. Proc. Gulf Caribb. Fish. Inst. 33: 253-266.•Menzies, R.A., and, J.M, Kerrigan.1979. Implications of spiny lobster recruitment patterns of the Caribbean – A biochemical genetic approach. Proc. Gulf Caribb. Fish. Inst. 31: 164-178. Funding to support this work

was provided by NSF-TUES grant DUE-1043468

Background:•The Caribbean Spiny Lobster, Panulirus argus, population structuring is complicated by the long-range dispersal of the planktonic larvae, called phyllosoma.•Two theories of recruitment have been postulated, the Pan-Caribbean Panmictic theory (Lyons 1980) and the Closed System Theory (Menzies et al. 1979).•The Sargasso Sea may serve as critical habitat in acting as a corridor between distant populations.

Purpose:To investigate the influence of selected environmental parameters onphyllosoma distribution, as well as genetic and life stage structuring in theSargasso Sea in order to understand Panulirus argus population dynamics.