Sustainable life with our aquatic neighbors the dolphins of Sarasota Bay

Transcription

1 Sustainable life with our aquatic neighbors the dolphins of Sarasota Bay Photo: June 2012 Randall Wells, Director and the staff, students, and collaborators of the Chicago Zoological Society s Sarasota Dolphin Research Program

2 Sustainability: the quality of not being harmful to the environment or depleting natural resources, and thereby supporting long-term ecological balance

3 Just another cute dolphin picture Nicklo (grandmother) 62 yrs old BlackTipDoubleDip (associate) 59 yrs old Eve (mother) 14 yrs old F286 (son/grandson) newborn Photo: June 2012

4 Just another cute dolphin picture can provide much insight about dolphin biology, behavior, and their needs for sustainability when the animals live in your backyard and have allowed you to study them for decades... Nicklo (grandmother) 62 yrs old BlackTipDoubleDip (associate) 59 yrs old Eve (mother) 14 yrs old F286 (son/grandson) newborn Photo: June 2012

5 Take home messages: 1. Long life spans. Nicklo (grandmother) 62 yrs old BlackTipDoubleDip (associate) 59 yrs old Eve (mother) 14 yrs old F286 (son/grandson) newborn Photo: June 2012

6 Take home messages: 1. Long life spans. 2. Long-term, year-round residency to local coastal waters - they truly are our neighbors; what we do in the neighborhood affects them. Nicklo (grandmother) 62 yrs old BlackTipDoubleDip (associate) 59 yrs old Eve (mother) 14 yrs old F286 (son/grandson) newborn Photo: June 2012

7 Take home messages: 1. Long life spans. 2. Long-term, year-round residency to local coastal waters - they truly are our neighbors; what we do in the neighborhood affects them. 3. Multiple concurrent generations of relatives. Nicklo (grandmother) 62 yrs old BlackTipDoubleDip (associate) 59 yrs old Eve (mother) 14 yrs old F286 (son/grandson) newborn Photo: June 2012

8 Take home messages: 1. Long life spans. 2. Long-term, year-round residency to local coastal waters - they truly are our neighbors; what we do in the neighborhood affects them. 3. Multiple concurrent generations of relatives. 4. Complex social structure and communication. Nicklo (grandmother) 62 yrs old BlackTipDoubleDip (associate) 59 yrs old Eve (mother) 14 yrs old F286 (son/grandson) newborn Photo: June 2012

9 Today s Presentation: Sarasota Dolphin Research Program History Methods and materials Findings Residency Biology and reproductive success Social structure Conservation Natural threats Threats from humans Mitigation efforts Education and outreach

10 Killer, Sarasota Bay s most frequently seen dolphin, born the same year as the SDRP, in Killer (FB90) - First identified in Seen more than 1,500 times - 9 calves born since calves survive: -Lizzie Borden (b. 1996, F) -Lorena Bobbitt (b. 1999, F) -Freddy Krueger (b. 2004, M) -Vader (b. 2009, M) -C909 (b. 2016,?) - 7 grand-calves (4 survive) Lizzie (F113) Bobbitt (F133) Freddy (F246) Vader (F270) 1 st calf, 1982, of 8

11 How are we able to know these details of a wild dolphin s life? Tagging began through Mote Marine Laboratory in Continued through the University of Florida during Research during continued through UCSC, DBRI. Since 1989, partnership led by Chicago Zoological Society. Since 1992, based at Mote Marine Lab present Photo-ID Tag Tags, Radio-Tag Sightings of 6 Identifiable Dolphins

12 Photo-Identification: Primary Tool Since 1977 Nicks and notches serve as fingerprints Bobbitt: >900 sightings since 1999 Sighting Database: - >49,200 sightings of dolphin groups - >718,000 archived photos - >147,700 individual identifications - >5,500 identifiable individuals - 96% of dolphins in Sarasota Bay are identifiable - >1,500 sightings of an individual - >45 years of sighting records for some

13 What have we learned? Multi-generational, multi-decadal, year-round residency FB43: Great-greatgrand-mother Communities in Tampa Bay FB37: Greatgrandmother F119: Grand-mother F125: Mother 1252: 2007 Calf

14 What have we learned? Multi-generational, multi-decadal, year-round residency 1. Mosaic of resident communities up and down the coast. FB43: Great-greatgrand-mother Communities in Tampa Bay FB37: Greatgrandmother F119: Grand-mother F125: Mother 1252: 2007 Calf

15 What have we learned? Multi-generational, multi-decadal, year-round residency 1. Mosaic of resident communities up and down the coast. 2. Current community of ~160 resident dolphins spans up to five concurrent generations. FB43: Great-greatgrand-mother FB37: Greatgrandmother Communities in Tampa Bay F119: Grand-mother F125: Mother 1252: 2007 Calf

16 What have we learned? Multi-generational, multi-decadal, year-round residency 1. Mosaic of resident communities up and down the coast. 2. Current community of ~160 resident dolphins spans up to five concurrent generations % of dolphins >15 yrs old have been seen for yrs. FB43: Great-greatgrand-mother FB37: Greatgrandmother F119: Grand-mother Communities in Tampa Bay F125: Mother 1252: 2007 Calf

17 What have we learned? Multi-generational, multi-decadal, year-round residency Number of Dolphins 1. Mosaic of resident communities up and down the coast. 2. Current community of ~160 resident dolphins spans up to five concurrent generations % of dolphins >15 yrs old have been seen for yrs. 4. Males can live to 52 yrs. 5. Females can live to >67 yrs! FB43: Great-greatgrand-mother FB37: Greatgrandmother F119: Grand-mother F125: Mother Communities in Tampa Bay Age-Sex Distribution: Average (for 148 Identifiable Dolphins) Unk Sex Females Males : 2007 Calf Adult, Unk Age Age Unknown Age Class (years)

18 Health Assessment Population Monitoring Basic Diagnostics and Samples Physical exam, ultrasound exam Reproductive assessment (ultrasound) Morphometrics Weight and body condition Lung function Hearing function Sampling for: CBC/blood chemistry/blood gases Serology, endocrinology Functional immunology Urinalysis Biotoxins Environmental contaminants Blowhole/lung microbes Genetics/paternity

19 Unique long-term datasets have led NOAA to use Sarasota Bay as a reference site for health and reproduction comparisons Mississippi Sound 2013 Barataria Bay, LA 2011, 2013, 2014, 2016, 2017 Sarasota Bay Reference Site

20 Deepwater Horizon Oil Spill Health, Survival, Reproduction Comparisons Photo by Alex Brandon/AP 1. Barataria Bay (BB) dolphins did not vacate BB during the oil spill. 2. BB dolphins had low adrenal hormone levels consistent with adrenal toxicity. 3. BB dolphins were 5 times more likely to have moderate to severe lung disease as compared to Sarasota Bay (SB). 4. Many BB dolphin disease conditions are uncommon, but consistent with oil exposure and toxicity. 5. Low annual survival (87% vs. 96%) and lower pregnancy success (20% vs. 83%) in dolphins from BB when compared to SB. Photo by Alex Brandon/AP

21 Wild bottlenose dolphin social structure was described first for Sarasota Bay dolphins Sarasota s dolphins do not live in families or pods they live in fluid groups, Mom, Dad, Kid exhibiting a fission/fusion society Pods

22 Wild bottlenose dolphin social structure was described first for Sarasota Bay dolphins Sarasota s dolphins do not live in families or pods they live in fluid groups, Mom, Dad, Kid exhibiting a fission/fusion society Pods Average group size: 3.2 dolphins (range: 1-30)

23 Wild bottlenose dolphin social structure was described first for Sarasota Bay dolphins Sarasota s dolphins do not live in families or pods they live in fluid groups, Mom, Dad, Kid exhibiting a fission/fusion society Pods Average group size: 3.2 dolphins (range: 1-30) Three basic social units: 1. Nursery groups, moms with most recent calves 2. Juvenile groups, mixed sex 3. Adult males, often in alliances

24 Who s your daddy? Observations, genetic samples unravel social structure, paternities Mom Dad Calf FB60 FB61 FB50 Killer (FB90) FB38 F122 FB48 F113 F106 F133 F246 FB6 F270 Lizzie (F113) FB10 F244

25 Adult males form strong pair bonds at sexual maturity Unusual feature in animal social systems: May increase reproductive success (from paternity testing) 2008 FB38: Died in 1999 Buddies of FB36: FB10: yrs old in 2011 (died in 2011) Mean age 1 st alliance bond formation 11.1±0.7 yrs Number of males/alliance 2.0 Mean annual COA of alliance partners 0.75±0.03 Average proportion of males in alliances in any given year 57.0±3.8%

26 Long-term study has allowed us to define life history and reproductive parameters Sexual Maturity: Females ~ 5-10 yrs Males ~ 10 yrs Seasonality: Most calves born May-July Gestation: ~ 12.5 months 83% of pregnancies live calves Mothers: 6-48 yrs old Up to 10 calves, to date Invest 3-6 yrs per calf Fathers (from paternity tests): yrs old Up to 7 offspring, to date

27 Social structure involves complex acoustic communication 1970s: Can dolphins speak English? Now: Signature whistle names Focal Animal Behavioral Observations Individual Recordings Digital Archival Acoustic Tag (DTAG) Playback Experiments

28 Ecological Perspective: Dolphin Food and Feeding Habits Seagrass meadows and mangrove fringing forests are crucial habitat features supporting prey for our local dolphins Sound-producing (soniferous) prey fish selected disproportionately

29 Gulf dolphins face an array of concurrent and cumulative threats Our program s focus is on understanding and mitigating threats

30 In our own Bay, Killer has experienced many changes during her lifetime 3.4 x People (Sarasota & Manatee Co.): 1970 = 220,334 vs = 748, x Boats (Sarasota & Manatee Co.): 1970 = 11,000 vs = 39,088 Siesta Key 1939 ~1950 Future Site Lido Key Bird Key 1960 Bird Key Bird Key Current Photos from Sarasota Water Atlas:

31 Understanding why dolphins die: Increasing threats from humans Working in partnership with Mote s Stranding Investigations Program

32 Anthropogenic Threats - Physical and Acoustic: Boat Disturbance and Collisions, Construction 1. ~40,000 boats registered in Sarasota Bay area 2. Boats pass within 100 m once every 6 min 3. 5% of dolphins have collision scars 4. Dolphins alter dive patterns and whistle patterns as boats approach record year for boat collisions (at least 4 1 death)

33 Entanglement in Commercial Fishing Gear: 11% of Sarasota s dolphins have entanglement scars, mostly obtained as calves or subadults F262, 1Mar16

34 Entanglement of F262 in Crab Trap Float Line: 6 years to the day after disentangling his 9-month-old sister, Nellie, from debris

35 Debris- Another Entanglement Threat: Poor Apparel Choice FB 248 Scrappy 8-yr-old Male In another unbelievable anecdote, {Carl} Hiaasen spoke of a dolphin that had found itself entangled in a discarded Speedo swimsuit. These are the true stories of a unique state, Hiaasen said, and they've been the inspiration for much of his work. Dolphin depantsing duty preserves dignity and a life By William Mullen, Chicago Tribune staff reporter Published August 16, 2006, 7:30 PM CDT Right Flipper Insertion

36 Recreational fishing gear entanglement and ingestion Biggest threat to local dolphins 2011: Yearling C797 - died 2012: 6-mo-old calf lost, too

37 2% of resident dolphins lost to recreational fishing gear in 2006: Dolphins were increasingly attracted to anglers and boaters because severe red tides depleted prey fish During : 1. Declines of >90% of some primary prey fish 2. 10% decline in dolphin abundance 3. Increased emigration, decreased immigration 4. Loss of 50% of 2-yr-old calves (weaning, most vulnerable) 5. Remaining 2-yr-old calves 20% underweight 6. Calves leave mothers at earlier age Fish abundance increased, gear deaths declined over next few years

38 Human Interactions are an increasing threat to dolphins Especially illegal provisioning, and interactions with bait and catch

39 Interventions and rescues Saving 1 dolphin at a time FB FMMSN Ginger Vidalia Skipper Nellie Scrappy Lizzie Speedy-2014 Parcel-2015 Bill-2016 Placida Toro

40 Human Interactions: Prevention is better than intervention HI spreads through dolphin social learning we try to mitigate through human education Lectures, Town Hall Mtgs Books 30-sec PSA

41 Don t Feed Wild Dolphins PSA/Website Available at: Dontfeedwilddolphins.org

42 Sum 13 PCBs (ppm, lipid normalized) Environmental contaminants are sequestered in blubber and released seasonally Likely have health and reproduction impacts Firstborn Males Firstborn Females Males Nulliparous Females Primiparous Females Multiparous Females Approx. threshold for health, reproduction impacts (Kannan et al, 2000, Jepson et al. 2005) Analyses by A. Borrell: Age (years) Wells, R.S., V. Tornero, A. Borrell, A. Aguilar, T.K. Rowles, H.L. Rhinehart, S. Hofmann, W.M. Jarman, A.A. Hohn, and J.C. Sweeney Integrating life history and reproductive success data to examine potential relationships with organochlorine compounds for bottlenose dolphins (Tursiops truncatus) in Sarasota Bay, Florida. Science of the Total Environment 349:

43 No. of Dolphin Deaths Emerging Threats: Climate Disruption 15 No. of Deaths Average Temperature Body Temperature January February March April May June July August September October November December Projections: Warmer waters will Limit dolphins cooling ability if water temperature equals or exceeds body temperature. 2. Require increased food intake to support increased metabolic rates. 3. Likely change prey species availability due to temperature, ph, depth, salinity changes. 4. Allow new pathogens to invade. 5. Prolong the seasonal exposure of dolphins to pathogens. 6. Increase HAB frequency and intensity. 7. Change frequency and intensity of hurricanes

44 Our Goal: Continued coexistence with our neighbors...through learning about the animals needs, and the potential implications of cumulative effects from multiple threats Thank you, for caring about Sarasota s dolphins and our shared environment! Please help yourselves to our brochures. For more information, visit:

45 Conservation Capacity Building: Sarasota Dolphin Research Program Interns/Trainees during Interns/trainees: 16 Hrs contributed: ~8,200 From: US, Brazil, Germany, Mexico, Spain Sweden, UK, Venezuela Interns (N = >60 non-us) Post-Grads (N = >20) Health Assessments (N = >100) Total SDRP trainees (non-health assessment): >330

46 Conservation Capacity Building through Graduate Research 35 PhD and 34 MSc Students have benefited from SDRP data collection opportunities, data, samples, or guidance over the years 2016 Doctoral Dissertations Completed: 5 Ongoing Dissertation Projects: 4 Master s Theses Completed: 2 Senior Theses Completed: 1

47 SDRP International Conservation Research Consultations Photo by Flip Nicklin