Blood, Bait, & Birds: the Horseshoe Crab, a Multiple Use Resource

Blood, Bait, & Birds: The Horseshoe Crab, A Multiple Use Resource

Mary-Jane James, PhD Graduate School of Oceanography University of Rhode Island [email protected] Older juveniles and Life Cycle young adults After adults reach sexual migrate to deeper maturity (9-10 years), they water. return to beaches to spawn Young in late spring to early juveniles summer. reside on intertidal flats. Males intercept females at spawning Males Female beaches as they come ashore to spawn.

Photo courtesy of Jane Brockman

Larvae hatch in Female Females dig a nest in sand and 2 to 4 weeks. Male deposit eggs. Males the fertilize eggs. Females may spawn multiple times laying up to 80,000 eggs.

Eggs develop in a nest on a beach. Development

Juveniles live & forage in mud at low tide Photo: E Hogan

16-17 molts and 9-10 years to become adults Molting juvenile Limulus

3 Slide courtesy of Jane Brockman The Resource: Shorebirds

At least 11 species of shorebirds feed on horseshoe crab eggs in Delaware Bay during the final legs of their northward migration.

Horseshoe crab eggs are an Slaughter Beach, DE important source of food in Delaware Bay where there are high surface densities of eggs on the beaches.

They provide essential energy and are important to the survival and reproduction of shorebirds.

Photo: K. Tuxbury The Resource: Ecotourism

• Over 1 million shorebirds converge on Delaware Bay each spring. • Thousands of tourists visit the Bay to watch the horseshoe crab spawning/shorebird phenomena. • Ecotourism related to horseshoe crabs provides millions of dollars annually • Virginia: $108 million • New Jersey: $87.5 million • Maryland: $83 million • Delaware: $11.5 million The Resource: Biomedical Industry

• Limulus Amebocyte Lysate (LAL), a biochemical constituent, is produced from horseshoe crab blood. o LAL detects bacterial pyrogens – fever causing endotoxins that are pathogenic to humans; o LAL is the standard test used to screen all medical equipment that comes in contact with blood or spinal fluid; o New applications include detection of bacterially contaminated food. • 100-300ml of animal’s blood is taken via cardiac sinus puncture (total blood volume is 200- 300ml). • ~30% mortality rate associated with bleeding and handling stress. • FDA mandates that bled crabs be returned to where they were captured within 72 hrs (new MA regulations allow bled crabs to be sold for bait). • Multimillion dollar industry (LAL can cost upwards of $5,000 per quart) – Annual revenues $60 million. • Four LAL producing companies in US. One on Cape Cod, three in Delaware Bay area. The Resource: Fertilizer & Animal Feed Commercial fisheries for fertilizer & animal feed • 1850’s to 1950’s • Peak harvests in Delaware Bay - 4 million crabs annually (1870’s & 1920’s to 1930’s) • Harvests declined to 100,000 crabs by the 1950’s • Decline due to: -Declining catches - Competition with commercial fertilizers - Public health concern • Between 1950 to 1980 – under reduced fishing pressure spawning populations slowly recovered The Resource: Bait Fishery

Commercial Fishery for Bait • 1980’s to present • Bait for American eel and whelk (conch) • Eel fishery targets egg-bearing females • 1990’s the commercial fishery increased dramatically mostly in the Mid-Atlantic but also in New England • Fishery has historically lacked coordinated, coast-wide monitoring, and regulation • Coast-wide landings have reached levels attained during fertilizer and animal feed fishery Whelk

American eel Fishery Regulations Prior to 1998

STATE REGULATIONS DC, CT, GA, ME, NC, PA, No harvest regulations, no reporting Federal waters

RI, MA, NY, FL No harvest regulations; no reporting; license required

VA License required; no limit; trawling & dredging prohibited

NJ Reporting & license required; no limit; Delaware Bay – only hand harvesting allowed

NH Reporting & license required; 10 crabs/day/person

DE Reporting & license; seasonal closures; vessel limit of 1500/day

MD Reporting & license required; annual quota 750,000 lbs; seasonal closures; 25 crabs/day/person

SC Reporting & license required; harvest limited to biomedical, scientific & educational purposes; minimum crab size & gear requirements Atlantic States Marine Fisheries Commission (ASMFC) Management Concerns

1. Horseshoe crab populations declined under heavy harvesting from 1860- 1950. Harvesting levels for eel & whelk bait in 1990’s were similar to those during fertilizer & animal feed fishery. 2. Crabs are easily harvested with minimum of financial investment. This makes them susceptible to over-harvesting. 3. Long maturation rates (9-10 yrs) creates a lag for population recovery. 4. Population data (trawl & spawning surveys, egg counts) existing prior to 1998 lacked standardization and were of little informative value. 5. No regulations in many of the states where they are harvested. ASMFC Mandatory Compliance

• Interstate Fishery Management Plan for Horseshoe Crab (ASMFC 1998) • Regulations for commercial fisheries (bait & biomedical harvests) • Monitoring programs • Law enforcement to implement regulations • Annual reports on fishery • Reduce 2000 bait landings by 25% below 1995-1997 levels (MA, RI, CT, NY, NJ, DE, MD)

The National Park Service has supported research (2001-2013) to survey spawning horseshoe crabs and investigate movement patterns. at several coastal parks (Cape Cod NS (MA), Fire Island NS (NY), Gateway NRA (NY) & Sagamore Hill NHS (NY). At the same time, other agencies (Fish & Wildlife Service, MA Div. Marine Fisheries, MA Audubon) also started monitoring programs. Department of the Interior (USFWS & NPS) & the Lawsuit Cape Cod NS • Horseshoe crabs had been harvested for biomedical uses & bait on Cape Cod (MA) within Pleasant Bay & Monomoy Pleasant Bay NWR since the 1970’s. • 1999 – The Department of Interior (Cape Cod NS & Monomoy NWR) re-evaluated their position on the Monomoy NWR horseshoe crab harvest within their boundaries. • 2000 - Cape Cod NS & Monomoy NWR closed their waters to horseshoe crab fishing. • 2000 - Department of Interior was sued by biomedical harvester & biomedical company (Associates of Cape Cod).

But why did the Department of Interior stop the harvest... Federal Regulation Regulation 36 CFR* 7.67- Shellfishing by permit from the appropriate town is permitted in accordance with applicable Federal, State, and local laws.

Regulation 36 CFR 2.2 - Prohibits the taking of wildlife except as authorized by hunting. Prohibits feeding, touching, teasing, frightening or intentional disturbing of wildlife nesting or breeding. Prohibits possessing unlawfully taken wildlife or portions thereof.

Authorities and Exceptions Commercial Activities: Engaging in or soliciting any business in park areas, except in accordance with provisions of a permit, is prohibited.

Research: A specimen collection permit may be issued if: – Official Representative of scientific organization or educational institute; – For purpose of research, monitoring; – Only to meet park management goals.

*CFR: Code of Federal Regulations I’m not a fish or Whatshellfish… I amam wildlife! I? Is a horseshoe crab fish or shellfish?

Photo: C. Roman Taxonomy Kingdom: Animalia , Phylum: Arthropoda , Subphylum: Cheilcerata, Class: Merostomata, Order: Xiphosurida, Family: Limulidae , Genus: Limulus, Species: polyphemus

Technically horseshoe crabs are neither fish, shellfish, or crustacean (Class Crustacea) – they are more closely related to spiders and scorpions than true crabs. Massachusetts Definition of Shellfish & Fish M.G.L. Chapter 130: Defines “Shellfish'‘ as clams, conchs, limpets, mussels, oysters, periwinkles, quahaugs, razor clams or razor fish, scallops, sea clams, sea quahaugs, sea scallops and winkles. Defines “Fish'', any animal life inhabiting the ocean or its connecting waters including any crustacean or marine fish, whether free swimming or free moving, and any shellfish or sea worms, whether or not imbedded in the soil. All provisions of the chapter relative to fish shall, so far as apt, apply also to lobster meat and crab meat after the same has been taken from the shell. Federal definition for Wildlife Wildlife means any member of the animal kingdom and includes a part product except fish. Fish means any member of the subclasses Agnatha, Chondrichthyes or Osteichthyes or any mollusk or crustacean found in saltwater. Horseshoe Crab Research At Coastal National Parks Funded (2000-2002, 2008-2010, 2012-2013) by the National Park Service

Cape Cod Cape Cod NS • Spawning surveys conducted on Bay Cape Cod (2000 to 2010); and at Nauset Estuary Long Island NPS units (2012-2013) MA Pleasant Bay in collaboration with other agencies. Monomoy NWR • Traditional tagging & acoustic CT Sagamore Hill telemetry were used to determine NHS movement patterns of crabs in

NY Nauset Estuary, Pleasant Bay (Cape Fire Island NS (Great South Bay) Cod, MA), Great South Bay (NY) & Jamaica Bay (NY) Gateway NRA Atlantic (Jamaica Bay unit) Ocean NJ Photo: J. Balliett US Fish & Wildlife Cooperative Tagging Program

Female crab

Measure prosomal (carapace) width Attach tag with a unique tag number, Male crab record date and tagging location Record sex

Re-sighted tagged crab at When a tagged horseshoe crab is seen, the public can report the tag number Fire Island NS either online or call the toll-free number: 1-888-LIMULUS

Pewter “reward” pin Beach Surveys • Spawning surveys are done during the full and new moon high tides in May & June, during the day & at night. • Data collected includes number of spawning crabs (by sex), cluster size (number of crabs in a cluster), and single crabs. • The time and length of the surveys are standardized so an Index of Spawning Activity (ISA) can be calculated. Spawning & Egg Densities Pickering Beach, DE • In Delaware Bay large congregations of spawning crabs are common. Egg densities are high.

• In Southern New England spawning indices and egg densities are much lower. Spawning Index (# females m-2) 1 Photo: Jane Brockman

Talisman Beach, Fire Island, NY 0.5

SpawningIndex 0 Cape Cod Long Island, Jamaica Delaware South NY Bay,NY Carolina 2500 Egg Density Deep sediments (5-20cm) Surface sediments (0-5cm) Pleasant Bay, MA 2000 1500 1000

500 Mean egg abundance Mean 0 Cape Cod Long Island, NY Jamacia Bay, NY Delaware Cape Cod Cape Cod NS Spawning Sex Ratios Bay (the ratio of females to males on spawning beaches)

Nauset Estuary Site Historic 2000 Recent (1950’s) to 2002 (2008-2102) Pleasant Bay Cape Cod Bay (MA) 1 to 2.4 1 to 2.9 1: 1.7 Monomoy NWR (MA) -- 1 to 1.9 1: 1.8 Monomoy NWR Nauset Estuary (MA) -- 1 to 1.6 1: 1.3

CT Pleasant Bay (MA) 1 to 2.5 1 to 5.8 1: 8.1 Jamaica Bay (Brooklyn, NY) -- -- 1 : 3.8

NY Talisman (Fire Island, NY) -- -- 1 : 2.3 Talisman 50 Jamaica Bay Atlantic Ocean 25

Percent females on spawning beaches at Percent female Percent 0 other Cape Cod areas Historic, 1950s 2000-2002 2008-2009 • Pleasant Bay (MA) has highly male skewed sex ratios • Other Cape Cod sites have sex ratios of 1 female to 1-3 males • Delaware Bay, Long Island spawning sex ratios are 1 female to 2-4 males • Unharvested populations (ME, FL) are 1 female to 2 males Tagging In Pleasant Bay, MA Evidence for a localized population

• 2027 crabs tagged in Pleasant Bay by URI/NPS in 2008-2009. • 16% overall recapture rate; 12% live recapture rate (324 tags re-sighted). • 88% of recaptures found within 2.5km of original tagging location. • All recaptures, except 1, were observed in Pleasant Bay. • No crabs tagged in other areas (Monomoy NWR, Cape Cod Bay) have been reported as recaptured in Pleasant Bay.

60 Pleasant Bay Recaptures 2010-2011 50 2009 40 2008

Photo: K. Medeiros 30 20

10 Percent of recapturesofPercent 0 Same Less greater Same Less greater site 2.5km 2.5km site 2.5km 2.5km

Photo: K. Medeiros Recaptured in same year Recaptured in subsequent years Tracking crabs underwater with acoustic telemetry

Sonar tracking tag on crab • Transmitter emits a unique acoustic signal; • Crabs tracked using a hydrophone and continuously tracked with Submersible Ultrasonic Receivers (SUR); • Transmitters can be detected up to 500m (about 1/3 of a mile) – detection in shallow water is ~50-100m; • SURs scan for signals at 1-2 min intervals and store data; • Some crabs also tagged with continuous depth & temperature data logger tags; Listening for sonar signals in • All crabs tagged with US Fish & Wildlife button tags. Pleasant Bay

Sonar tracking tag & button tag on crab SUR buoy Impact of Biomedical Bleeding on Horseshoe Crab Movement and Physiology

• Tracked bled and unbled crabs with acoustic telemetry in summer 2001: • Bled crabs had a random movement patterns (disoriented behavior). • Control crabs had directional movement patterns. • No difference in rate of movement, but trend for bled crabs to move slower. • Evidence from another bleeding study indicates protein concentration of hemolymph (blood) remains significantly lower in bled and handled crabs than in unbled control crabs.

Bled crabs 4

Control crabs 3

+ + SE) 1 1 No detections -

2 min 1

Rate of movement (m movement of Rate 0 Bled Control Horseshoe Crab Movement In Pleasant Bay Released Crab # 128 Last detection Crab # 127

Released May 2009 Released Aug May 2009 June 2010 2009 April 2010

June June 2009 2009

Sept-Oct 2009 Oct-Dec 2009

Sept July-Sept 2009 2009

Location of SURs (Submersible Ultrasonic Receivers) Horseshoe Crab Movement In Pleasant Bay Released Crab # 156 May-June Crab # 162 2010 Last detection Released May 2009

Released May 2009

May 2010 April 2010

June June 2009 Aug 2009 2009 Oct-Nov 2009

Oct-Dec May 2010 2009 June 2010

Sept July 2009 2009

Location of SURs (Submersible Ultrasonic Receivers) Horseshoe Crab Movement In Pleasant Bay - 2008-2010 Released Crab # 110 Last detection Crab # 155 Released May 2009

Released May 2010 May 2008

July 2009

June 2010 Nov 2009

June 2008 May 2010 Aug 2009 July 2010 Oct 2009 Aug 2010 Aug 2010

Aug 2009

Sept 2009

Location of SURs (Submersible Ultrasonic Receivers) Full moon Depth-temperature & telemetry data for crab #134 New moon Crab overwintered in Pleasant Bay

F. Found dead on spawning beach Temperature Depth 29 May 2010 1 25 A: Tagged Marsh 2-3 C: Lower Pleasant Bay E: Pochet Inlet 11 May 2009 23 Sept-7 Oct 2009 23 & 29 May 2010 F 0 20 E -1

D -2 15 B A C D: W Hog Is.  -3 19 May 2010 B: E Hog Is. 10 -4 7 July 2009 C (m) Depth

-5 5 Temperature

-6 0 C: Lower Pleasant Bay -7 C: Lower Pleasant Bay 21 Nov 2009 24 April-2 May 2010

-8 -5

09 10

10 09

09 10

- -

Jul

Jan

Jun

Oct

Feb

Apr Apr

Sep

Dec

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Mar -

- -

May May

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25 20

SURs out of water for winter

James-Pirri, M.-J. 2010. Seasonal movement of the American horseshoe crab (Limulus polyphemus) in a semi-enclosed bay on Cape Cod, Massachusetts (USA) as determined by acoustic telemetry. Current Zoology 56:575-586 (invited paper, special issue on horseshoe crab behavior). Important Research Findings Related to Resource Management • Biomedical bleeding may alter normal behavior and may long lasting (several weeks) impacts on physiology. • Spawning “hot spots” – Three beaches (two of them in Pleasant Bay) represented 57% of total spawning on Cape Cod. – Evidence from Long Island also indicates spawning hot spots. • Spawning sex ratios are skewed in Pleasant Bay – Historical (1950’s) sex ratios were lower (1:2.5 female to male) compared to ratios observed over past 10 years, and are different from other areas of Cape Cod. Possibly related to the long history of harvest in the bay.

• Evidence for localized populations on Cape Cod – Sex ratios differed among regions – High percentage of crabs recaptured at or near (within 2km) of original tag location – Evidence for spawning site fidelity – Little movement among bays – Crabs overwinter in Pleasant Bay

• This may be the model for SE New England populations in semi-enclosed Bays (Great Bay, NH; Pleasant Bay, MA)

• Localized populations require different management techniques to maintain sustainable populations (regional vs. local stocks). Thanks! • National Park Service – Cape Cod NS, Sagamore Hill NHS, Fire Island NS, Gateway NRA • NPS Park and Regional staff • NPS Bio Technicians • Student Conservation Association Interns • The many volunteers and others who helped… Questions? The Lawsuit – a timeline • 1999 – Cape Cod NS & Monomoy NWR (Dept. of Interior- DOI) made aware of illegal harvesting of horseshoe crabs. • 2000 (spring) – Fishery is closed & active protection of horseshoe crab as a wildlife species is implemented in federal waters. • 2000 (spring) – DOI is sued by biomedical harvester & biomedical company (Associates of Cape Cod, ACC) over fishery closure. • 2000 – Court injunction allows biomedical harvester to collect crabs in federal waters. • 2001 – Courts rule in favor of the DOI (horseshoe crabs are wildlife), fishery closure within NPS was legal. ACC withdrawals lawsuit. But Monomoy NWR had unresolved issues regarding authenticity of their boundaries. Court injunction allows biomedical harvester to harvest crabs within USFWS Refuge. • 2001-2002- Biomedical harvester appeals decision in Superior Court, but it is sent back to District Court because of Monomoy NWR’s boundary issues. •2002 to 2005 - Monomy NWR resolved boundary issues. Fishery remains closed in federal waters. •2006 – State closes Pleasant Bay to bait harvest, biomedical harvest still allowed in non- federal waters. • 2009-2011- MA instituted more conservative regulations - harvest prohibited during peak spawning, minimum size limits. • Present – Federal waters closed to harvest, Pleasant Bay closed to bait harvest, biomedical harvest is allowed in non-federal waters. Passive Acoustic Telemetry Number of transmitter detections over time 91% of crabs detected, ~58,000 detections, 922 “crab-days” or daily detections Percent of daily Number X detections <10% 10-20% 20-30% <30% of crabs Spawning 2009 Post-spawning 2009 Fall 2009 Spawning 2010 (May-June) (July-August) Sept-Dec (Late-April-June) 31 crabs detected 35 crabs detected 23 crabs detected 26 crabs detected 7

6 11 4 9 16 14 11

12 14 10 17 8 6 1 1 3 8

10 2 7 But… Some horseshoe crabs do move out of the Bay

Crab #78: Stayed in upper bay in June, 2008

Passed into lower bay on June 30, 2008

Recaptured by trawler on July 21, 2008