NANFA-- heat tolerant sculpins

Fritz Rohde (Fritz.Rohde_at_ncmail.net)
Tue, 31 Jul 2001 16:38:21 -0400

Dave Neely mentioned that several of you have gotten Cottus
caeruleomentum from the coastal plain of the Delmarva Peninsula, not
typical habitat for sculpins. Rudy Arndt and I published a paper in
Brimelyana (a not very widely-distributed journal) in 1981 on a
population of this species in DE. At the time (1971-1974) we were
working in our spare time on a survey of the state's freshwater fishes
and were extremely excited to discover what we thought was the first
known coastal plain population of Cottus bairdi (now caeruleomentum). I
think we did collect ours first but some friends were the first to
officially report it's occurrence on the Peninsula, just over the state
line in MD. Since we were scooped on this point and because it was an
interesting population, we decided to investigate it's life history.
Some of the high points were that individuals in this population were
shorter-lived and attained sexual maturity at a smaller size than what
was known in other studied populations. Only 2 age groups (maybe a
third) were found - that year's young and fish who had survived the to
the first year (only about 33% did). They spawned in Feb and Mar. They
had fewer eggs (size dependent) than did most other populations and all
eggs matured at the same time. Water temperature in late July reached
20 C (68 F), not too warm considering it's location. I always felt
these coastal plain populations were unique and perhaps Dave will be
able to prove that conclusively one day.

Fritz Rohde
Wilmington, NC

/-----------------------------------------------------------------------------
/"Unless stated otherwise, comments made on this list do not necessarily
/ reflect the beliefs or goals of the North American Native Fishes
/ Association"
/ This is the discussion list of the North American Native Fishes Association
/ nanfa_at_aquaria.net. To subscribe, unsubscribe, or get help, send the word
/ subscribe, unsubscribe, or help in the body (not subject) of an email to
/ nanfa-request_at_aquaria.net. For a digest version, send the command to
/ nanfa-digest-request_at_aquaria.net instead.
/ For more information about NANFA, visit our web page, http://www.nanfa.org