Dr. Benjamin Morales, Senior Scientist, and Janneth Padilla: ECOSUR, Chetumal, Mexico

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1 Title: Contaminants in endangered manatees (Trichechus manatus) in Mesoamerica: Risk assessment using a sentinel species Principal Investigators: Drs. John Reynolds and Dana Wetzel Senior Scientists Mote Marine Laboratory 10 Ken Thompson Parkway Sarasota, Florida Phone: Fax: reynolds@mote.org dana@mote.org Key Collaborators: Dr. Benjamin Morales, Senior Scientist, and Janneth Padilla: ECOSUR, Chetumal, Mexico Dr. James Powell, Director Aquatic Conservation, Wildlife Trust, Sarasota, Florida Ms. Nicole Auil, Wildlife Trust, Belize City, Belize Dr. Ester Quintana, Guatemala City, Guatemala Dr. Fardin Oliaea, Research Associate, Mote Marine Laboratory, Sarasota, Florida Dr. Cristina Fossi, University of Siena, Siena, Italy Project Duration: Three years Project Summary: The United Nations Environment Programme is working with scientists and managers from the wider Caribbean region to develop a Marine Mammal Action Plan. That plan will reflect that: (a) great concern exists about levels and effects of contaminants on marine mammals and other organisms (including people); (b) there are inadequate data available regarding contaminants or their effects in the region; (c) due to their long lifespans, physiology, and other attributes, marine mammals can serve as excellent sentinel species to help assess threats to both environmental and human health; and (d) due to their wide inshore distribution, endangered status, and multiple effects of human activities, research and conservation of manatees is a high regional priority. The 28

2 area in which manatees are most abundant in the Caribbean includes the coasts of Mexico and Belize (i.e., Mesoamerica). In that area, long-term programs to assess ecology, body condition, and habitat use of manatees exist in southeastern Mexico (under the direction of Dr. Benjamin Morales) and Belize (under Dr. James Powell and Ms. Nicole Auil). At least some individual manatees have been documented to use waters of both countries. In a pilot study, we have recently found that manatees captured and released in Chetumal Bay, Mexico, contained surprisingly high tissue levels of polychlorinated biphenyls (PCBs) and a wide range of chlorinated pesticides; in fact, one individual had PCB levels that exceed toxic threshold levels for dolphins. Our proposed project seeks funding to develop a comprehensive program to complement and supplement existing programs to accomplish the following objectives: (a) assess levels and effects of a wide range of organic contaminants (pcbs, chlorinated pesticides, toxic components of oil called polycyclic aromatic hydrocarbons [PARs] and flame retardants [polybrominated diphenyl ethers or PBDEs)) in Mesoamerican manatees; (b) use sophisticated biomarkers of exposure to assess cellular and subcellular effects of contaminant exposure associated with particular levels of contaminants found in the manatees; (c) assess contaminant levels in sediments in areas where it appears that manatees may be exposed to very high environmental contaminant concentrations; (d) conduct formal health risk assessments for manatees of Mesoamerica based on results of the contaminant and biomarker analyses; (e) provide training in contaminant monitoring to Mesoamerican scientists; and (f) develop a public awareness and education program for regional residents based on our findings. To achieve these goals we will work with the established manatee research programs and scientists to take small biopsy samples from a number of GPS-tagged manatees (for which physical locations over time are known) from Mexican and Belizean waters on a repeated basis (e.g., once a year) to evaluate changes in organic contaminant levels for individuals of known size class, reproductive condition, body condition, and gender over time. Sediments and fish in the nearby Mesoamerican rier Reef System (MBRS) have high levels of certain organochlorines and hydrocarbons---some levels within the same order of magnitude as those found in fish from the Portland (OR, USA) Harbor Superfund site. Our goal is acquire insights about contaminant locations, levels, and effects by repeatedly sampling a long-lived, endangered marine mammal whose life history attributes and coastal habitat make it a good sentinel species for human and ecosystem health. 29

3 Table 1. Biometric information on animals analyzed for PAHs, PCBs and OCPs in Chetumal Bay, Mexico and SW Florida, USA. Location Sample 10 Date Sex/Age 1 Length Weight Sample (g) Lipid (%) (cm) (kg) (blubber/blood) (blubber/blooc Chetumal Bay, Mexico Between north cays and coast Guerrero Lagoon Channel Guerrero Lagoon Channel Mouth of Creek River Mouth of Creek River BCH-034 BCH-035 BCH-036 BCH-037 BCH-038 BCH-046 BCH-047 BCH-048 BCH-049 3/26/2006 3/26/2006 3/27/2006 3/28/2006 3/29/2006 3/19/2007 3/20/2007 3/22/2007 3/22/2007 M/A-J MIA F/J F/A MIA M/A-J / / / / / / /2.84* 26.02*/2.84* 26.02*/2.84* * 26.02*/ */ */ */ */16.61 Mean ± St. dev ± 0.10/ ± ± B4± 5.33 SW Florida, USA Boca Grande Pass Orange River San Carlos Bay Placida Harbor Estero Bay Placida Harbor Gasparilla Sound Estero Bay Caloosahatchee River Charlotte Harbor Lemon Bay Estero Bay Peace River San Carlos Bay San Carlos Bay Caloosahatchee River Alligator Creek Spreader Canal Caloosahatchee River Orange River Big Carlos Pass Caloosahatchee River Lemon Bay Mullock Creek Lemon Bay Gasparilla Sound Lemon Bay MSW0315 MSW0320 MSW0346 MSW0347 MSW0353 MSW0355 MSW0356 MSW0357 MSW03 MSW0359 MSW0364 MSW0377 MSW0387 MSW03130 MSW03143 LPZ MSW03169 MSW03176 MSW0412 MSW0421 MSW0450 MSW0477 LPZ MSW0491 MSW0529 MSW0533 MSW0561 2/ /7/2003 3/26/2003 3/27/2003 4/ /2/2003 4/2/2003 4/2/2003 4/3/2003 4/3/2003 4/5/2003 4/10/2003 4/14/2003 6/16/2003 7/ / /4/ /26/ /23/2004 6/21/ /9/ /29/ /2005 3/6/2005 3/7/2005 3/21/2005 F/J F/J MIA MIA M/A-J F/A F/A-J M/A-J F/A M/A-J MIA F/A F/A-J M/A-J F/J F/J F/A MIA MIA F/A M/A-J N/A o ± ± 15, Sex/Age: M=Male; F-Female; J-Juvenile; A=Adult; A-J - an individual that approaches the published length at which sexual maturity occurs (i.e., 275 em) *= the mean lipid% for samples with no measurable lipid amounts due to small sample sizes. 30

4 Table 2. PCB and OCP concentrations for animals sampled in Chetumal Bay, Mexico and SW Florida, USA. See Table 1 for more detailed biometric information. Location Sample 10 Blubber Blood ~:PCBs LPCBs LOCPS LOCPS LPCBs LPCBs LOCPS LOCPS Ilg/g Iw Ilg/g ww Ilg/g Iw Ilg/g ww Ilg/g Iw Ilg/g ww Ilg/g Iw Ilg/g ww Chetumal Bay, Mexico Between north cays and coast Guerrero Lagoon Channel Guerrero Lagoon Channel Mouth of Creek River Mouth of Creek River BCH-034 BCH-035 BCH-036 BCH-037 BCH-038 BCH-046 BCH-047 BCH-048 BCH ' 0.49' ' 1.' 0.38' 3.86' 1.39' > > > > > Mean ± St. dev. 1.81± ± ± ± ± ± ± ± 0.01 SW Florida, USA Charlotte Harbor San Carlos Bay MSW0359 MSW Mean ± St. dev ± ± ± ± 0.03 ' = the mean lipid% for samples with no measurable lipid amounts due to small sample size 31

5 List of Figures: Figure 1: Figure 2: Figure 3: Figure 4: Figure 5: Figure 6: Figure 7: Figure 8: LPCBs and LOCPS (Ilg/g lw) in the blubber and blood of free-ranging manatees from Chetumal Bay, Mexico and stranded manatees from SW Florida. Different letters indicate statistical differences. Error bars represent one standard deviation. Mean relative abundance of PCB congeners in the blubber of stranded manatees from SW Florida (top) and free-ranging manatees from SE Mexico (bottom). Mean relative abundance of OCPs in the blubber of stranded manatees from SW Florida, USA (top) and free-ranging manatees from Chetumal Bay, Mexico (bottom). Error bars represent one standard deviation. Mean relative abundance of PCBs in blubber and blood of free-ranging manatees from Chetumal Bay, Mexico. Congener numbers are in accordance with the International Union of Pure and Applied Chemistry (IUP AC) nomenclature. Error bars represent one standard deviation. Mean relative abundance of OCPs in blubber and blood of free-ranging manatees from Chetumal Bay, Mexico. Error bars represent one standard deviation. Principle components analysis (vector plot) in blubber of stranded manatees from SW Florida and free-ranging manatees in Chetumal Bay, Mexico. Congener numbers are in accordance with IUP AC nomenclature. Principle components analysis (variable plot by location) of PCB congener abundance in blubber of stranded manatees from SW Florida and free-ranging manatees in Chetumal Bay, Mexico. Congener numbers are in accordance with IUP AC nomenclature. Principle components analysis of OCPs (vector plot) in blubber of stranded manatees from SW Florida and free-ranging manatees in Chetumal Bay, Mexico. Congener numbers are in accordance with IUP AC nomenclature. Figure 9: Principle components analysis (variable plot) of OCP abundance in blubber of stranded manatees from SW Florida and free-ranging manatees from Chetumal Bay, Mexico. Figure 10: Global comparison of mean LPCB and LOCP concentrations in the blubber of male marine mammals. * Manatees (SE, Mexico): Maximum concentrations were used. PCBs ranged from Ilg/g lw (mean ± sd: 2.06 ± OCPs ranged from Ilg/g lw (mean ± sd: 3.40 ± 7.52). 32

6 :r i c D 5.00 i c CD u c D D l:pcb EOCP Blood Blubber c,e Blubber Mexico Florida SAMPLE MATRIX and LOCATION Figure 1: ~PCBs and ~OCPs (J.lg/g lw) in the blubber and blood of free-ranging manatees from Chetumal Bay, Mexico and stranded manatees from SW Florida. Different letters indicate statistical differences. Error bars represent one standard deviation. 33

7 0.20., ] Floridll.. 1l c "1J C ::J ~ ~ 'ii Qj '" 0. 1O ~ o.ool_, 0.30, Mexico ; ljl~~~~... _.... _ ,! I ~ ~ ~ r II 1(' Tj I i ~ r. I T l 1 r oo,a,_,-j,.,a.,.j,,1,',.,,i T, ',,1,.,',i,l,l,a,",lo).,'... J,I,I,...,.,.J,.,i, ''' ' ~ ' ''' '. ri.t'' '~T.,I,i.l.l, JI' 4',":./ ~"$ "'~{/I ojoflo.. ~ 4'4'.jo ~,.~ ~ 4>,~,~~",,,:,p,~,.t)-.f-l'~'$,4'~$$'''$'~'<f,*''~,f,4'(f'~'#~./'<l'''''...,,, -I'"~",4'", PCB IUPAC Nu mber Figure 2. Mean relative abundance of PCB congeners in the blubber of stranded manatees from SW Florida (top) and free-ranging manatees from SE Mexico (bottom). 34

8 0. 25 ~ ~ i Florida j ~. ~~lilla, I,, _,...---,_, _,.., ~, ' Me xico 0.30 i Figure 3. Mean relative abundance of OCPs in the blubber of stranded manatees from SW Florida, USA (top) and free-ranging manatees from Chetumal Bay, Mexico (bottom). Error bars represent one standard deviation. 35

9 IUPAC No. Figure 4. Mean relative abundance of PCBs in blubber and blood of free-ranging manatees from Chetumal Bay, Mexico. Congener numbers are in accordance with the International Union of Pure and Applied Chemistry (IUP AC) nomenclature. Error bars represent one standard deviation. 36

10 0.4) 0.3) II c ' c :J O.Zl ~ ~ 0.15 i.. O.tJ '" 0.35 o Blubber Blood O.as Figure 5. Mean relative abundance ofocps in blubber and blood of free-ranging manatees from Chetumal Bay, Mexico. Error bars represent one standard deviation. 37

11 I ~ 0) C) :! N u (II u Factor 1 : 28.30% Figure 6. Principle components analysis (vector plot) in blubber of stranded manatees from SW Florida and free-ranging manatees in Chetumal Bay, Mexico. Congener numbers are in accordance with IUP AC nomenclature. 38

12 8 6 ~ m C) """ N Q... U til LL Mexico o Mexico M ~ ico o Mexico Mexico Meoco Mexico L 0 Mexico 0 ~ _ Mexicg o I I I I t -6-8 ~--~ ~--~----~ ~ ~--~ o B Factor 1: 28.30% Figure 7. Principle components analysis (variable plot by location) of PCB congener abundance in blubber of stranded manatees from SW Florida and free-ranging manatees in Chetumal Bay, Mexico. Congener numbers are in accordance with IUP AC nomenclature. 39

13 1.0 #. Cl Cl co N u ro u Factor 1 : 27.83% Figure 8. Principle components analysis of OCPs (vector plot) in blubber of stranded manatees from SW Florida and free-ranging manatees in Chetumal Bay, Mexico. Congener numbers are in accordance with IUP AC nomenclature. 40

14 ~ CD N... B u (OJ LL Mexico o Mexico Mexic ~e ico Mexico ~exlco MexlcoO Mexb o o Mexico -2-1 o Florida Of:"lorida Factor 1: 27.83% Figure 9. Principle components analysis (variable plot) of OCP abundance in blubber of stranded manatees from SW Florida and free-ranging manatees from Chetumal Bay, Mexico. 41

15 . IPCB o mcp Dugong (NE Australia) Manatees (GOM, FL) _ Documented toxic threshold fcl' dolphins Beluga whales (Beaufort-Chukchi Sea) Manatees (SE, Mexicot Rough-toothed dolphins (GOM, FL) Bottlenose dolphins (NW.Atlantic) Concentl1ltlon (pg/g Iw) Figure 10. Global comparison of mean I,PCB and I,OCP concentrations in the blubber of male marine mammals. * Manatees (SE, Mexico): Maximum concentrations were used. PCBs ranged from Ilg/g lw (mean ± sd: 2.06 ± l.95. OCPs ranged from Ilg/g lw (mean ± sd: 3.40 ± 7.52). 42