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Posted by Alex Harper on 16:03:10 12/18/12
In Reply to: razorbill report 12/17/12 and request posted by Cindy Meyer
One of the issues regarding food availability is this:
Colder water has a higher capacity to hold dissolved oxygen. It might be counterintuitive, but our warm waters are less capable of sustaining nearly as many organisms as cooler water can, such as the waters off the NE United States and off of eastern Canada. The colder waters of the Razorbills' usual wintering grounds are teeming with food items. This is also the reason that the largest number of species and individuals of pelagic birds are found in the coldest waters.
Hurricane Sandy is almost surely the culprit for this event. Sandy could have drastically altered the benthic environment in the northwest Atlantic, killing off crustaceans and fish. It may be possible that there was a heavy uplift of sediments. The suspended sediments could have interfered with light penetration into the upper layers of the bays and ocean, and slowed production of phytoplankton, an important prey item for fish that the Razorbills might feed on.
This is only my speculation. At any rate, I can't imagine that a species accustomed to a very different niche space can winter successfully in our comparatively stagnant waters.
Alex
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