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Extinction risk and conservation of the world’s sharks and rays
Overall chondrichthyan extinction risk is substantially higher for sharks, rays, and chimaeras than for most other vertebrates, and only one-third of species are considered safe.
Reproductive biology of skates, Bathyraja(Ishiyama), along the eastern Bering Sea continental slope
Evidence is presented that suggest skates may be limited to as little as one and as many as 13 spawning seasons, depending on the species, and that senescence may occur in older individuals.
Sharks, Rays, and Chimaeras of California
This guide is the only complete reference to the sharks, rays, and chimaeras found in California's waters - from the intertidal zone to 500 miles offshore. Species accounts give information on
Standardized diet compositions and trophic levels of skates (Chondrichthyes: Rajiformes: Rajoidei)
Results from this study support recent assertions that skates utilize similar resources to those of other upper trophic-level marine predators, e.g. seabirds, marine mammals, and sharks.
Breaking with tradition: redefining measures for diet description with a case study of the Aleutian skate Bathyraja aleutica (Gilbert 1896)
The resultant new index, the Prey-Specific Index of Relative Importance (%PSIRI), is introduced and recommended to replace %IRI for its demonstrated more balanced treatment of the relative measures of prey quantity, and less erroneous behavior across taxonomic levels of identified prey.
Comparative feeding ecology of four sympatric skate species off central California, USA
The studied skate assemblage appears to consist primarily of generalist crustacean and fish predators that exhibit high dietary overlap at similar sizes, and it is possible that resource competition among skates and groundfish species has been reduced because of considerable recent declines in the biomass of upper trophic level groundfishes.
Reproductive biology of catsharks (Chondrichthyes: Scyliorhinidae) off the west coast of southern Africa
Five southern African catshark species were caught between Walvis Bay, Namibia, and Cape Agulhas, South Africa, from 50 to 1016 m deep, and the reproductive mode of four species was oviparous, whereas G. polli exhibited aplacental viviparity.