Distribution and reproductive biology of deep-sea scyliorhinids off central California.
Distribution and reproductive biology of deep-sea scyliorhinids off central California. |
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Catsharks (family Scyliorhinidae) are the largest and one of the most diverse
families of living sharks, totaling 15 genera and approximately 106 species
distributed worldwide. Two genera of scyliorhinids predominate the deep-water
slope region that typifies the eastern North Pacific, Apristurus and Parmaturus.
Three scyliorhinids of these genera have been reported in the eastern North
Pacific, the brown catshark, A. brunneus, the long-nose catshark, A. kampae,
and the filetail catshark, P. xaniurus.
Because of the depth at which these species are typically found, knowledge
is extremely limited concerning the life history of all three of these catsharks.
There has been little life history study of these three species north of Point
Dume, California (34°N latitude), and the occurrence of these scyliorhinids
as incidental catch in commercial fishing operations warrants the research of
their biology and distribution to gauge the need for fisheries management. In
addition, these scyliorhinids inhabit a deep-sea environment off coastal California,
an environment in which it is difficult to define seasonal cues that may incite
reproduction or to locate food resources to sustain relatively large vertebrate
macrofauna. It is the purpose of this project to describe the systematics, distribution,
and reproductive biology of A. brunneus, A. kampae and P. xaniurus in the eastern
North Pacific.
Through the cooperation of the NOAA Southwest Fisheries Science Center laboratory
in Santa Cruz, CA and NOAA Northwest Fisheries Science Center (NWFSC) laboratories
in Newport, OR and Seattle, WA, and by observers of the Pacific States Marine
Fisheries Commission, Brooke has managed to collect over 1000 samples along
the entire Pacific coastline of the United States, from British Columbia to
San Diego, CA. This will enable investigation of changes in distribution and
population ecology along latitudes as well as depth. Brooke has had the opportunity
to assist in the NWFSC annual slope cruise as a field biologist. In addition,
specimens in collections at the California Academy of Sciences, University of
Washington, Natural History Museum of Los Angeles County, Museum of Comparative
Zoology, and Scripps Institution of Oceanography were examined and included
in distribution analysis.
Brooke obtained her BS in Marine Biology in 1998 after completing her undergraduate
thesis on the biochemical properties of elasmobranch blood coagulation. Having
abandoned all prospects of free time or having a social life after developing
an unhealthy affinity for these charismatic little catsharks, she is now finishing
graduate study (19th grade) at MLML in Spring 2005. She presented findings of
her research on the distribution and reproduction of A. brunneus, A. kampae,
and P. xaniurus at the American Elasmobranch Society/American Society of Ichthyologists
and Herpetologists Joint Meetings in June-July 2003 and July 2004 and at the
7th Indo-Pacific Fish Conference in Taipei, Taiwan in May 2005. Brooke will
begin doctoral study in functional morphology, biomechanics, and comparative
physiology at Harvard University in Fall 2005.
Created by: Lewis Barnett
Comments: webmaster@mlml.calstate.edu
Last Revision: 3 August 2005
