GinglymostomidaeNurse SharksChris Bedore

October 2, 2007

Taxonomy and EtymologyOrder Orectolobiformes

Family Ginglymostomidae

Genus Ginglymostoma Nebrius Pseudoginglymostoma

ginglymostoma= “hinge mouth”

Morphology

General characteristics• 2 spineless dorsal fins, 1 anal fin

•barbels on nostrils, nasoral groove

• broad, flat head

• small spiracles behind small eyes

• ventral caudal lobe small or lacking

• small, multicuspid teeth

• small gill slits, 4th and 5th almost overlapping

Morphology

Morphology

Distinguishing characteristics

•large caudal fin with strong terminal lobe and subterminal notch

• coloration- lacks patterns (saddles, stripes, spots)

Morphology

MorphologyGinglymostoma cirratum**~300cm TLrounded finsyellow to grey-brownlong barbelsNebrius ferrugineus~315cm TLlong barbelsangular finsshades of brownPseudoginglymostoma brevicaudatum~75cm TL, dark brownshort barbelsdorsal fins same size

Habitat, Distribution, Lifestyle•subtropical and tropicalG. cirratum: especially E. Pacific and Atlantic

•continental waters

•associated with coral and rocky reefs, sandy bottom, lagoons, mangroves <1 to 12m

•basically benthic, but do swim around

•very common in Gulf of Mexico and FL Keys

Behavior• like to hide in caves, under reefs

• nocturnal

Behavior• docile, not aggressive

will bite divers when provoked!

Behavior• social, will rest in groups or piles of 20-30 individuals

Behavior• although docile, spin on line when hooked (like an alligator)

Reproduction• ovoviviparous, large yolk sac

Reproduction• 20-30 pups/litter, at different stages due to ovulation

• 5-6 month gestation, mating in May-July

• Males mature 10-15 years, Females 15-20 years (~150cm TL)

Prey/Feeding habits• benthic prey

crustaceans, squid, teleosts, stingrays

• suction feeders- small mouth, large pharynx

• will eat any bait

Human Importance• Nuiscance in some places- raid bait traps• Not aggressive (unless provoked)

• Economic importance:tourismex: Shark and Ray Alley, Belize

aquarium

not sportfish because sluggish, but flesh is edible

Conservation Status• abundance has decreased• exhibit site fidelity- anthropogenic activities threaten habitat (esp. mating /nursery grounds)

• IUCN Redlist:

G. cirratum- data deficient; likely decreasing due to habitat

N. ferrugineus- decreasing; bycatch in coastal fisheries

P. brevicauda- data deficient, may be decreasing due to bycatch

ResearchJeff Carrier (Albion College) and Wes Pratt (Mote Marine Lab)http://www.albion.edu/sharklab/default.asp

probably most reproduction info of any species knownmultiple observed matings in FL Keys/Dry Tortugas- model for repro. behavior (see Pratt and Carrier, 2001)

seasonal closures of mating grounds in Dry Tortugas(see Carrier and Pratt, 1998)

Jose Castro (Mote Marine Lab)- detailed biology of the nurse shark(see Castro, 2000)

Research

Carrier J.C. and H.L. Pratt, Jr. 1998. Habitat management and closure of a nurse shark breeding and nursery ground. Fisheries Research 39:209-213.

Castro, J.I. 1983. The sharks of North American waters. Texas A&M Univ. Press, College Station, TX. 180p.

Castro JI. 2000. The biology of the nurse shark, Ginglymostoma cirratum, off the Florida east coast and the Bahama Islands. Environ. Biol. Fish. 58: 1-22.

Compagno, L., M. Dando, and S. Fowler. 2005. Sharks of the World. Princeton University Press, Princeton, NJ. 368p.

Klimley A.P. 1980. Observations of courtship and copulation in the nurse shark, Ginglymostoma cirratum. Copeia 1980(4):878-882.

Pratt H.L. and J.C. Carrier. 2001. A review of elasmobranch reproductive behavior with a case study on the nurse shark, Ginglymostoma cirratum. Environmental Biology of Fishes 60:157-188.

Selected Works