Whales and Barnacles

From: tom tilas (TKTilas@comcast.net)
Date: Sat Sep 27 2003 - 14:55:34 EDT

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    Question: Is there a symbiotic relationship between whales and

    Dear Ann,
    There does not seem to be a symbiotic relationship between whales and
    barnacles unless you consider humpback whales using their barnacles as
    weapons for fighting during times of competition symbiotic. A response
    by Dr. Phil Clapham explains the relationship:
    There is no symbiosis between whales and barnacles as far as we can
    tell. Barnacles use the whale as a substrate, essentially hitching a
    free ride and filter-feeding off the water around the whale. If
    anything, they are a disadvantage for the whale since they create some
    drag in the water.

    There is a rather better case for symbiosis - albeit speculative - in
    right whales. Right whales (genus Eubalaena - now recognized by many of
    us as three species: E. glacialis in the North Atlantic, E. japonica in
    the North Pacific, and E. australis in the southern hemisphere) have
    odd-looking bumps on their heads called callosities. These are patches
    of roughened skin ("cornified epithelium") which are natural and part of
    the whale. However, the callosities (and some other places on the
    body)are covered with hundreds of thousands of parasites called cyamids
    ("whale lice" is the common term). We know these are parasitic because
    their guts have been found to contain whale skin. However, the
    suggestion has been made that they may serve a cleaning function
    (getting rid of dead skin). A more bizarre idea is that the cyamids may
    somehow cue the whale in to densities of its prey (zooplankton, mostly
    copepods) around it by somehow changing their behavior. The idea is
    that, by sensing the activity of the copepods, the right whale may be
    able to judge the density of prey right in front of it (since right
    whales need high-density patches of copepods). There is no real direct
    evidence for this idea, but it's an interesting hypothesis!

    Good luck on your project!
    Kim Marshall

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