This article is stuffed with a
lot of conclusions that are really assumptions and surely cannot be properly
tested from the data. However, the bird
is surviving and will easily expand once our fishing technology is improved and
we figure out how to rid ourselves of non biodegradable plastic. Actually, if there were ever a cause that
deserves the attention of the UN it is the plastics problem.
It is noted that climate change
has been working in the favor of the albatross. The changes themselves appear to be part of
normal variation in the Southern Hemisphere.
Beyond that we simply do not have much data yet and the picture will
certainly look a lot different in another twenty years whatever happens.
I must admit I am getting testy
when every report on natural science blames everything on effectively the
weather.
Largest bird alters its foraging due to climate change
by Staff Writers
Researchers on Crozet fit a transmitter on a wandering albatross.
Credit: David Gremillet/CNRS.
Wandering albatrosses have altered their foraging due to changes in
wind fields in the southern hemisphere during the last decades. Since winds
have increased in intensity and moved to the south, the flight speed of
albatrosses increased and they spend less time foraging. As a consequence,
breeding success has improved and birds have gained 1 kilogram.
These are the results of the study of an international research team
published in the latest issue of the Science journal. However, these positive
consequences of climate change may last short if future wind fields follow
predictions of climate change scenarios, researchers warn.
For this study, biologists had combined data on the duration of
foraging trips and breeding success over the last 40 years, as well as foraging
and body mass over the last 20 years of wandering albatross (Diomedea exulans)
breeding in Crozet
Islands Madagascar and Antarctica ).
It belongs to the French Southern Territories and it is located in the
windiest part of the Southern Ocean. The new findings are the result of an
international research team from the French National Centre for Scientific Research (CNRS-CEBC)
and the German Helmholtz-Centre for Environmental Research (UFZ).
Thanks to miniaturised tracking devices, researchers were able to
track the foraging movement of albatrosses at a distance of 3500 kilometers
from the colony. They found that albatross have altered their search patterns
following changes in wind conditions over the past two decades. Females
used increasingly more poleward and windy areas for foraging. As a consequence
their travel speed increased while the total distance covered during foraging flights
did not change.
"This means that they spend less time at sea while incubating the
egg and thus the breeding success increases" explains Dr. Henri
Weimerskirch of the French National Centre for Scientific Research (CNRS-CEBC).
Researchers were surprised that both females and males have increased
their body mass in one kilogram, which corresponds approximately to one tenth
of their total body weight. This could be not only a result of shorter
incubation periods on the nest,
but also an adaptation to windier conditions.
"The wandering albatross Crozet population has decreased as a
result of adult mortality on longline fishing in subtropical waters, especially
females since they favour warmer subtropical waters in the north compared to
the more southerly distribution of males" says Dr. Maite Louzao Arsuaga,
who has been modelling albatross movement from 2009 to 2011 at the UFZ.
"Due to the changing wind conditions, females are now foraging in
more southward areas where such fishing is
not that widespread". However, the positive effects of changing
environmental conditions of the last decades will not last in the future.
Climate scenarios predict that westerly winds will move even further south by
2080 and wandering albatrosses might have to fly further to find optimal
conditions for flying.
The total population of the wandering albatross is currently estimated
at around 8,000 breeding pairs. All populations have shown a decrease at some
stage over the last 25 years. This endangered species is threatened
primarily by incidental catch in fisheries, especially longline fishing at sea,
whereas the introduction of alien species (such as rats or cats) are a key
conservation threat for the species on breeding colonies.
Additionally, the accumulation of anthropogenic debris such as plastic
and fishing hooks on albatrosses have negative effects on their populations.
Thus, it is important to continue with monitoring programs of population
trends and distribution at sea, as well as to undertake effective conservation
measures. The foraging habitat of wandering albatrosses is managed by more than
one Regional Fisheries Management Organisations, which makes it difficult to
implement conservation measures for the species.
The wandering albatross has fascinated people for centuries. With a
wingspan of over three meters and a half, it is the largest seabird in the
world, surpassing just the Andean condor (Vultur fulvus). This elegant sailor,
which spends most of its life flying,
breeds on remote subantarctic islands over the Southern Ocean. They travel
thousand of kilometers searching for fish and cephalopods like squids, often
following ships and feeding on offal.
The plumage of wandering albatrosses is variable, whitening with age.
The maximum known age is 55 years old. Since the rearing of chicks takes a
whole year, they breed only every second year
Apart from the study published in the latest Science issue, the
research team has identified the key marine areas for the conservation of
wandering albatrosses in the southern Indian Ocean
published in 2011 in the Journal of Applied Ecology. This study provided the
first map to support the future development of a network of priority protected
areas in the southern part of the Indian Ocean ,
which are based on habitat predictions.
"Because the species has no natural enemies and is at the top of
the food web, it is particularly well suited as an indicator of the health of
marine ecosystems," says Dr. Thorsten Wiegand from the UFZ, who supervised
thework of
Dr. Maite Louzao.
"This could help not only a single species, but the underlying
biodiversity associated with pelagic key habitats to protect Southern Ocean.
Moreover, we have developed methods of habitat modelling broadly applicable and
can be used to assess changes in species distribution within the current global
change scenario."
Henri Weimerskirch, Maite Louzao, Sophie de Grissac, Karine Delord
(2012): Changes in
Wind Pattern Alter Albatross Distribution and Life-History Traits. Science.
335: 221. 13 January 2012; DOI: 10.1126/science.1210270; Louzao, M., Pinaud,
D., Peron, C., Delord, K., Wiegand, T., Weimerskirch, H. (2011): Conserving pelagic
habitats: seascape modelling of an oceanic top predator. J. Appl.
Ecol. 48 (1), 121 - 132.
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