Continuing research:
Information on satellite data:
"prey distance" hypothesis v. the "feeding site quality" hypothesis
Scientist believed for a long while that the distances birds (such as the
albatross) had to cover in order to find prey was directly proportional to
the number of offspring. This is also known as the "prey distance theory."
Recently however, scientist have used satellite tracking to see exactly how
and where albatrosses forage for food. They have found that if the quantity
of the prey is high, then the distance does not really affect reproductive
rates, suggesting that this "feeding site quality" hypothesis is accurate.
They found that "foraging trips by all three species often exceeded three
weeks in duration and covered distances over 3000 km roundtrip" (Fernandez
and Anderson 1999)
I found this article to be interesting mainly because it showed a way to
test a hypothesis using remote data sensing systems: satellites. This
may be a possible way to monitor systems or processes with species.
The ability to link/prove/disprove "cause and effect" ideas that at first
seem completely unrelated was what caught my attention.
Source:
Fernández, A.P. and Anderson, D.J. 1999. Foraging behavior of Galapagos
albatrosses revealed by satellite tracking and its relationship to reproductive
rate. Proceedings of the American Association for the Advancement of Science,
Pacific Division 18 (1): 53.
Saving the Albatross (and possibly other sea birds):
According to the article, "longlining is the single greatest threat to the
world's seabirds." Many seabirds, such as the Albatross (including Espanola's
Waved Albatross) are effected by long-line fishing. The birds often
fly just behind the longlining boats and try and snag the bait on the hooks
as it is "released." Longlining is very popular now-a-days because
it costs less than regular fishing methods (nets, crates). Among other
problems dealing with long- problem is that they try and eat the bait, but
get caught on the hooks which then drag them underwater until they drown.
Once the lines are "set," they sink, and the birds can't get to them.
Possible Solutions presented by the article (low cost, too!) on how to minimize
seabird deaths:
-"Towing bird-scaring (or tori) lines behind the vessel. These have plastic
streamers tied to them that flap in the wind and scare birds away from the
baited fishing line."
-"Using an underwater setting tube. These set the fishing line underwater
out of reach of the birds."
-"Tying enough weights to the fishing line so that it sinks more quickly
out of reach of the birds"
-"Using thawed not frozen bait as it sinks more quickly."
-"Dying the bait blue. This puts birds off eating it."
-"Setting lines at night. Most albatrosses feed mainly by day."
(all above solutions are directly from Birdlife International (2004))
The above measures are low-cost as well as favorable to the fishermen; the
less bait that gets eaten by the birds, the greater chance of catching more
fish.
The Agreement for Conservation of Albatrosses and Petrels (CAPA) is an agreement
to reduce seabird deaths due to longline fishing. "Five countries have
both signed and ratified the Agreement (Australia, Ecuador, New Zealand, Spain
and South Africa), guaranteeing its entry into force on 1 February 2004."
This fact may be of particular importance to us because it means that Ecuador
has shown its willingness to compromise when important environmental
issues are put forth to be solved.
The ideal goal for our group would be to find a feasible, cost-effective
solution, and explore all the positive and negative aspects. Translation:
if we do all the research, then the plan has a greater chance of being taken
seriously, and possibly address on the governmental level (or even international
level).
Source:
Birdlife International. (2004) Save the Albatross. <http://www.birdlife.org/action/campaigns/save_the_albatross/index.html>
Downloaded October 2, 2004
1000 tortoises to Espanola:
The population on Espanola went down to fifteen individuals at one point.
They were taken and bred in captivity. By the year 2000, 1000 turtles
were released on Espanola -- a major jump from fifteen. Galapagos National
Park Service and the Charles Darwin Foundation have worked together (in Reptile
Rearing Center located on Santa Cruz Island) to restore tortoise populations.
This is valuable to know, because it means we have a successful method for
restoring species. Although it requires long years of hard work and
dedication, the results are incredible. Overall it is cheaper and healthier
to prevent the species from becoming endangered/nearly extinct than to recreate
the entire population.
Sources
Charles Darwin Foundation. (2000) More than 2000 tortoises have returned
home. From the 1999 Annual Report. <http://www.darwinfoundation.org/articles/ar00040046.html>
Downloaded October 23, 2004.
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