BASELINE HEALTH PARAMETERS AND SPECIES COMPARISONS AMONG FREE-RANGING ATLANTIC SHARPNOSE (RHIZOPRIONODON TERRAENOVAE), BONNETHEAD (SPHYRNA TIBURO), AND SPINY DOGFISH (SQUALUS ACANTHIAS) SHARKS IN GEORGIA, FLORIDA, AND WASHINGTON, USA
نویسندگان
چکیده
منابع مشابه
The sexually dimorphic cephalofoil of bonnethead sharks, Sphyrna tiburo.
Sexually dimorphic head shape is common in vertebrates from teleosts to mammals. Herein we document that cephalic sexual dimorphism is also found in the cartilaginous fishes (Chondrichthyes). Male bonnethead sharks develop a prominent bulge along the anterior margin of the cephalofoil at the onset of sexual maturity. This contrasts with the uniformly rounded anterior margin of adult females and...
متن کاملRetinofugal pathways in fetal and adult spiny dogfish, Squalus acanthias.
Retinofugal pathways in fetal and adult spiny dogfish were determined by intraocular injection of [3H]proline for autoradiography. Distribution and termination of the primary retinal efferents were identical in pups and adults. The retinal fibers decussate completely, except for a sparse ipsilateral projection to the caudal preoptic area. The decussating optic fibers terminate ventrally in the ...
متن کاملMitochondrial DNA diversity and divergence among sharpnose sharks , Rhizoprionodon terraenovae , from the Gulf of Mexico and Mid - Atlantic Bight
-The Atlantic sharpnose shark, Rhizoprionodon terraenovae, is a small coastal shark that is harvested in both directed and nondirected fisheries throughout its range. Because pups of this species are found both along the southeastern U.S. Atlantic coast and the Gulf of Mexico, it is possible that multiple isolated breeding stocks exist. Restriction fragment length polymorphism analysis ofmitoch...
متن کاملField hearing measurements of the Atlantic sharpnose shark Rhizoprionodon terraenovae.
Field measurements of hearing thresholds were obtained from the Atlantic sharpnose shark Rhizoprionodon terraenovae using the auditory evoked potential method (AEP). The fish had most sensitive hearing at 20 Hz, the lowest frequency tested, with decreasing sensitivity at higher frequencies. Hearing thresholds were lower than AEP thresholds previously measured for the nurse shark Ginglymostoma c...
متن کاملLongevity of Atlantic Sharpnose Sharks Rhizoprionodon terraenovae and Blacknose Sharks Carcharhinus acronotus in the western North Atlantic Ocean based on tag-recapture data and direct age estimates
Longevity of Rhizoprionodon terraenovae and Carcharhinus acronotus in the western North Atlantic Ocean was examined using direct age estimates from vertebral sections and tag-recapture data. Time-at-liberty ranged from 7.7-14.0 years (mean =10.1) for R. terraenovae and 10.9-12.8 years (mean =11.9) for C. acronotus. Maximum estimated longevity was determined to be 19.8 years through tag-recaptur...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Journal of Wildlife Diseases
سال: 2012
ISSN: 0090-3558
DOI: 10.7589/0090-3558-48.2.295