Conservation biology of the smalltooth Conservation biology of the smalltooth sawfish: science to help save the USA's sawfish: science to help save the USA's

first endangered elasmobranchfirst endangered elasmobranch

Tonya Wiley and Beau YeiserCenter for Shark Research

Elasmobranch Conservation Biology Program

What are sawfish?What are sawfish?• Members of the family Members of the family

PristidaePristidae• A type of rayA type of ray• All possess the distinctive All possess the distinctive

toothed rostrum or sawtoothed rostrum or saw• Inhabit tropical and Inhabit tropical and

subtropical coastal, subtropical coastal, estuarine and fresh watersestuarine and fresh waters

• Seven known species, six Seven known species, six in in PristisPristis

• Taxonomy is still confused Taxonomy is still confused and needs revisionand needs revision

• Historically largetooth and Historically largetooth and smalltooth sawfish in the smalltooth sawfish in the USUS

Pristis pectinata Pristis pectinata in US in US waterswaters• Historically common Historically common

from the Mexican from the Mexican border to Carolinasborder to Carolinas

• Summer migrations Summer migrations from Florida and from Florida and Georgia north to Georgia north to Carolinas and Carolinas and Virginia (and Virginia (and sometimes even sometimes even Long Island)Long Island)

The decline of The decline of P. pectinataP. pectinata

• From 1900 to 2000 From 1900 to 2000 the population is the population is estimated to have estimated to have declined in excess of declined in excess of 95%95%

• Extirpated from most Extirpated from most of its historic range, of its historic range, only occurs regularly only occurs regularly in southwest Florida in southwest Florida and Florida Keysand Florida Keys

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) Louisiana sawfish abundance

The causes of the The causes of the P. P. pectinata pectinata declinedecline• Mortality in fisheries Mortality in fisheries

(commercial and (commercial and recreational), recreational), especially due to especially due to netsnets

• Loss of important Loss of important nearshore habitat, nearshore habitat, especially for the especially for the juvenilesjuveniles

• Late maturing, Late maturing, produce few youngproduce few young

Male Size at Male Size at MaturityMaturity

Previous data

270 cm (~9 feet)

New data between

320-372 FL

340-395 STL

(~11 feet)

March 2002-Nine Mile Bank

March 2003-Nine Mile Bank

May 2007-East Cape Canal

July 2007-Florida Keys

May 2007-East Cape Canal

The USA’s first endangered The USA’s first endangered elasmobranchelasmobranch

• TOC petitioned for ESA TOC petitioned for ESA listing in 1999listing in 1999

• Status reviewStatus review• April 1, 2003 April 1, 2003 P. pectinata P. pectinata was added to was added to

the US Endangered the US Endangered Species ListSpecies List

• Also:Also:– Protected in Florida Protected in Florida

since 1992since 1992– Critically Endangered Critically Endangered

listing by IUCNlisting by IUCN– Endangered Listing by Endangered Listing by

AFSAFS– CITES Appendix 1CITES Appendix 1

Mote research on Mote research on P. P. pectinatapectinata

• Goal is to provide the Goal is to provide the scientific basis for scientific basis for population recoverypopulation recovery– Determination of Determination of

distribution and distribution and abundanceabundance

– Identification of critical Identification of critical habitathabitat

– Population geneticsPopulation genetics– Population and habitat Population and habitat

modeling modeling

Outreach & EducationOutreach & Education• Ask the public to report Ask the public to report

any captures or any captures or sightings of sawfishsightings of sawfish

• Texas to North CarolinaTexas to North Carolina

• Public can easily identify Public can easily identify sawfish correctlysawfish correctly

• Due to rarity, the public Due to rarity, the public is a good way to sample is a good way to sample a wide area a wide area continuouslycontinuously

Sawfish encounters 1998-Sawfish encounters 1998-20072007

Sawfish encounters 1998-Sawfish encounters 1998-20072007

Size and depth distributionsSize and depth distributions

• Full size range of Full size range of animals reportedanimals reported

• Majority of animals Majority of animals reported are juvenilesreported are juveniles

• Small Small P. pectinataP. pectinata limited to shallow limited to shallow waters (<5m)waters (<5m)

• Larger Larger P. pectinataP. pectinata have a wider depth have a wider depth distributiondistribution

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Estimated length (cm)

Fre

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y = 0.0297x - 2.4076

R2 = 0.1345

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Field SurveysField Surveys

Gillnet and seine Rod and reel

Longline

Spring Juvenile SurveysSpring Juvenile Surveys

•13 sawfish captured

•11 YOY

•2 Immature

•2 new nursery locations (Huston Coves & Bay)

Grocery Creek

Mud Bay

Last Huston Bay

Huston Coves

East Cape Canal

Whitewater Bay

Eagle Key

Habitat use through manual Habitat use through manual trackstracks

Habitat use by juvenile Habitat use by juvenile P. P. pectinatapectinata• Movements are Movements are

strongly influenced by strongly influenced by tide tide

• Remain in very shallow Remain in very shallow water (<50 cm)water (<50 cm)

• Relatively small home Relatively small home range over short range over short periods (days) and periods (days) and often longer periods often longer periods (months)(months)

High tide

Mid tide

Low tide

Habitat use by juvenile Habitat use by juvenile P. P. pectinatapectinata

VR 2 monitoring

1548

1549

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4/17/2003 0:00 4/18/2003 0:00 4/19/2003 0:00 4/20/2003 0:00 4/21/2003 0:00 4/22/2003 0:00 4/23/2003 0:00 4/24/2003 0:00 4/25/2003 0:00 4/26/2003 0:00 4/27/2003 0:00 4/28/2003 0:00 4/29/2003 0:00

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Site fidelity studiesSite fidelity studies•Use moored Use moored acoustic listening acoustic listening stations to record stations to record the the presence/absence presence/absence and movements of and movements of sawfishsawfish

Satellite telemetry of large Satellite telemetry of large P. pectinataP. pectinata

• Wildlife Wildlife Computers PAT Computers PAT tags used to tags used to examine longer-examine longer-term term movements of movements of sawfishsawfish

• Archive location, Archive location, depth and temp. depth and temp. data and then data and then send via satellite send via satellite after pop-upafter pop-up

Satellite TaggingSatellite Tagging

Four sawfish:

400 cm TL F - Nov 2006

382 cm TL F - Nov 2006

210 cm TL F - May 2007

330 cm TL M - May 2007

Satellite Tagging-ResultsSatellite Tagging-ResultsDays Since Release

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06A0532 Released Nov 14 2006 06A0533 Released Nov 15 2006

•Two females

•Data from November 2006 to February 2007

•Similar depth profile

•Data still being analyzed

Starting this Fall…Starting this Fall…

• Monitor the movements, residency time, possible aggregations and habitat use of large sawfish in Everglades National Park and the Florida Keys using BRUVS, and PAT and SPOT tags

BRUV’s

Critical habitat for Critical habitat for P. P. pectinatapectinata

• The next step is to The next step is to determine critical determine critical habitathabitat

• Depth, salinity, Depth, salinity, temperature, temperature, substrate etcsubstrate etc– Juvenile areasJuvenile areas

• PuppingPupping• Growth to maturityGrowth to maturity

– Adult areasAdult areas• FeedingFeeding• MatingMating• AggregationsAggregations• MigrationsMigrations

Critical habitat of Critical habitat of P. P. pectinatapectinata

• Major factors appear Major factors appear to be:to be:– Estuarine areas Estuarine areas

(especially around (especially around river months and lower river months and lower reaches of rivers)reaches of rivers)

– Shallow banks along Shallow banks along mangrove shorelines mangrove shorelines (juveniles)(juveniles)

– Deep channels through Deep channels through shallow areas (adults)shallow areas (adults)

Genetics CollaborationsGenetics Collaborations

• Demian Chapman (Pew Institute for Ocean Science) and Kevin Demian Chapman (Pew Institute for Ocean Science) and Kevin Feldheim (The Field Museum)Feldheim (The Field Museum)

• Objective 1:Objective 1: Determine whether multiple discrete breeding Determine whether multiple discrete breeding populations of sawfish remain in the U.S. that should each be populations of sawfish remain in the U.S. that should each be managed managed independently and locally independently and locally or whether there is only or whether there is only one breeding population that should be managed one breeding population that should be managed as a unit, co-as a unit, co-operatively by federal and state agenciesoperatively by federal and state agencies. (philopatry, . (philopatry, relatedness)relatedness)

• Objective 2:Objective 2: Assess the population history of smalltooth sawfish Assess the population history of smalltooth sawfish in their SW Florida “stronghold” and determine whether they in their SW Florida “stronghold” and determine whether they have suffered a loss of genetic diversity that may compromise have suffered a loss of genetic diversity that may compromise their ability to survive and reproduce in the future.their ability to survive and reproduce in the future.

• Mahmood Shivjy-Nova Southeastern UniversityMahmood Shivjy-Nova Southeastern University• ObjectiveObjective: DNA forensics to identify species of fins and rostra in : DNA forensics to identify species of fins and rostra in

tradetrade

AcknowledgementsAcknowledgements• National Marine Fisheries ServiceNational Marine Fisheries Service• Disney Wildlife Conservation FundDisney Wildlife Conservation Fund• Florida Fish and Wildlife Conservation Florida Fish and Wildlife Conservation

CommissionCommission• Munson FoundationMunson Foundation• Florida Power & LightFlorida Power & Light• National Fish and Wildlife FoundationNational Fish and Wildlife Foundation• National Geographic Conservation TrustNational Geographic Conservation Trust• John Ball Zoo SocietyJohn Ball Zoo Society• Mote Scientific FoundationMote Scientific Foundation