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Hi Bob
Thanks for the answer. I was also interested in the question of paratenic hosts.
The eels were captured in fykenets, and varied between 421 and 850 mm.
I'm still wondering if the daphnia became aggregated in the fyke net and the eels simply responded to this (I really don't trust eel dietary studies based on fyke nets). Unfortunately, there is no other way we can sample these particular lakes.
I'm a stable isotope ecologist so we will run these eels to see if they have a zooplankton signature...
All the best
Chris
-----Original Message-----
From: Scientific forum on fish and fisheries [mailto:[log in to unmask]] On Behalf Of [log in to unmask]
Sent: 18 November 2008 15:29
To: [log in to unmask]
Subject: Re: Anguilla anguilla feeding on Daphnia
Chris,
I've not heard of this, but am curious because crustaceans may be
intermediate or paratenic hosts for Anguillacola crassus, a parasite of
concern here in North America. How big were the eels? Thanks.
One note. We looked at stomach contents of American eels in the Roanoke
River, North Carolina, in 2000 and found a prevalent food item in eels up
to around 350 mm was small case-building caddisflies (Trichoptera), of a
sort that built their cases from Hydrilla verticillata leaves. Because the
cases were usually intact, are usually attached to a substrate, and the
eels were collected from dense patches of Hydrilla, it appeared the eels
had actively found and fed on the caddisflies. May be smaller food items
are more frequently utillized by eels than we'd previously thought.
Bob Graham
Environmental Biology
4111 Castlewood Road
Richmond, VA 23234
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Pager 7044
804 271-5377
Christopher
Harrod
<[log in to unmask] To
uk> [log in to unmask]
Sent by: cc
Scientific forum
on fish and Subject
fisheries Anguilla anguilla feeding on
<[log in to unmask] Daphnia
sunet.se>
10/04/2008 12:23
PM
Please respond to
Scientific forum
on fish and
fisheries
<[log in to unmask]
sunet.se>
Dear all
Another question about people's experience, this time about eels (Anguilla
anguilla & others).
A student of mine came has been working on a freshwater lake, and reported
that he was getting large numbers of Daphnia from yellow eel stomachs
(TL>400 - 800 mm).I rose my eyebrows and suggested that he was likely to be
mistaken, but to my surprise, he was right. Some individuals had stomachs
distended with the volume of Daphnia they had consumed. Now, I can imagine
glass eels feeding on zooplankton, but struggle to think of how yellow eels
would do this....
Has anyone ever recorded yellow eels feeding on Daphnia or read of reports
in the literature?
Thanks in advance
Chris
><> ><> ><> ><> ><> ><> ><> ><> ><> ><> ><> ><> ><> ><
Dr Chris Harrod
Lecturer in Fish and Aquatic Ecology
Queen's University Belfast
School of Biological Sciences
Medical Biology Centre
97 Lisburn Road
Belfast BT9 7BL
UK
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Tel: +44 (0) 28 909 72271
Mob: +44 (0) 79 77419314
Lab: +44 (0) 28 909 72106
Fax: +44 (0) 28 909 75877
http://www.qub.ac.uk/schools/SchoolofBiologicalSciences/Staff/DrCHarrod/
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