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More-Gull Barnacle Info

DV
Dennis Varza
Wed, Feb 29, 2012 8:23 PM

In response to recent e-mails

One can see this event anywhere from Milford to Norwalk where one can
get a good view.
Stratford Pt.
Stratford Sea Wall
Stratford Long Beach
Bridgeport Seaside Park
Bridgeport St. Mary's
Fairfield, Penfield Reef
Westport, Burying Hill Beach
Westport Sherwood Is. St. Pk.
Westport Compo Beach
Norwalk Calf Pasture Beach.

Jerry Connolly reported seeing Gulls and Terns feeding off the
eastern sound of fish larvae.
That is a different phenomenon. It is later in the season and include
Terns and fish larvae.
The barnacles are usually done before the terns show up.

What to call the "Food"

Plankton refers to any small organism that floats in the water column
not swim through it.

Phyoplankton are the plankton that are green. When looking at buoy
data there is a reading of Chlorophyl -A and that gives an estimate
of the amount of Phytoplankton It generally goes up in the spring
with the increase in sunlight. and the increase in nutrients from the
bottom.

The use of the word Bloom implies a refrence to Phytoplankton. This
may have an effect on the Barnacle Larvae.

Zoplankton are the animal part of the plankton. It can be anything
form fish larvae, crustacean larvae, worm larvae and assorted
multicellular organisms.
Then there is micro plankton. Plankton nets have a certain mesh size
which determine what gets caught or not. At some point they found
that using a finer net got them a lot more organisms then they
thought  was there.

Larvae are immature forms of organisms that are generally different
in morphology than the adults. ie. insect larvae, Frog larvae, Fish
larvae, Crustacean larvae. often time taxonomic identity is best done
by looking at the larvae. At one time Barnacles were considered
mollusks.

Could organisms other than barnacles be involves? Definitely, but it
would most likely be other places at other times. Blue Crabs? I can't
imagine crabs producing enough larvae to produce a drift of gulls
several miles long.

Over the past couple of years Larry Flynn John Barclay and myself
have been out on Larry's boat with nets and sampled the waters where
the gulls fed. Every time Barnacle Larvae. John has said that when he
was working on Greater Scaup, specimens would have their bellies full
of the larvae.

Barnacles go through several stages. the eggs hatch into a feeding
stage called the Nauplius After 6 months it transform into the Cyprid
stage. This is the stage being fed on. It look like tiny clams with
eyes and antenna, it does not feed and eventually attaches to a hard
surface. Towards the end of the event one will see the gull along the
rocky areas where the larvae settle out. The gulls will be scraping
the rocks with the side of their bills trying to get at them.

This is another case of Birders know one thing Marine Biologists Know
other things but little interaction takes place.

Dennis Varza
Fairfield

In response to recent e-mails One can see this event anywhere from Milford to Norwalk where one can get a good view. Stratford Pt. Stratford Sea Wall Stratford Long Beach Bridgeport Seaside Park Bridgeport St. Mary's Fairfield, Penfield Reef Westport, Burying Hill Beach Westport Sherwood Is. St. Pk. Westport Compo Beach Norwalk Calf Pasture Beach. Jerry Connolly reported seeing Gulls and Terns feeding off the eastern sound of fish larvae. That is a different phenomenon. It is later in the season and include Terns and fish larvae. The barnacles are usually done before the terns show up. What to call the "Food" Plankton refers to any small organism that floats in the water column not swim through it. Phyoplankton are the plankton that are green. When looking at buoy data there is a reading of Chlorophyl -A and that gives an estimate of the amount of Phytoplankton It generally goes up in the spring with the increase in sunlight. and the increase in nutrients from the bottom. The use of the word Bloom implies a refrence to Phytoplankton. This may have an effect on the Barnacle Larvae. Zoplankton are the animal part of the plankton. It can be anything form fish larvae, crustacean larvae, worm larvae and assorted multicellular organisms. Then there is micro plankton. Plankton nets have a certain mesh size which determine what gets caught or not. At some point they found that using a finer net got them a lot more organisms then they thought was there. Larvae are immature forms of organisms that are generally different in morphology than the adults. ie. insect larvae, Frog larvae, Fish larvae, Crustacean larvae. often time taxonomic identity is best done by looking at the larvae. At one time Barnacles were considered mollusks. Could organisms other than barnacles be involves? Definitely, but it would most likely be other places at other times. Blue Crabs? I can't imagine crabs producing enough larvae to produce a drift of gulls several miles long. Over the past couple of years Larry Flynn John Barclay and myself have been out on Larry's boat with nets and sampled the waters where the gulls fed. Every time Barnacle Larvae. John has said that when he was working on Greater Scaup, specimens would have their bellies full of the larvae. Barnacles go through several stages. the eggs hatch into a feeding stage called the Nauplius After 6 months it transform into the Cyprid stage. This is the stage being fed on. It look like tiny clams with eyes and antenna, it does not feed and eventually attaches to a hard surface. Towards the end of the event one will see the gull along the rocky areas where the larvae settle out. The gulls will be scraping the rocks with the side of their bills trying to get at them. This is another case of Birders know one thing Marine Biologists Know other things but little interaction takes place. Dennis Varza Fairfield