16 November 2006 -- Climate change is and will
increasingly have dramatic impacts on migratory species
from whales and dolphins to birds and turtles a new report
by the United Nations Environment Programme (UNEP) says.
Some species, like green turtles, are suffering higher
levels of tumours with the rise linked to warmer waters
that may be favouring infections.
Others, like the North Atlantic Right Whale, may be impacted
by a decline in their main food source-plankton-as a result
shifts in big ocean currents says the study launched at
the climate convention talks in Nairobi.
Meanwhile changes and losses in habitats have—and
are likely to increasingly have in the future—significant
impacts on species that migrate long distances.
The report, by UNEP’s Convention on Migratory Species,
has been compiled with support from the UK Department
of Environment, Food and Rural Affairs. It cites lower
water tables and more frequent droughts that will reduce
habitat for the Baikal Teal and foraging grounds for species
like the Aquatic Warbler.
Around a fifth of the bird species listed under the Convention
could be affected by rising sea levels, erosion and greater
wave action linked with climate change including the Lesser-White
Achim Steiner, UN Under-Secretary General and UNEP Executive
Director, said:” “Biodiversity—a term
for the range of animal, plant and other life on this
planet—is already suffering from a range of impacts
including over exploitation, loss and damage to habitats
and pollution. Unchecked, climate change will pile on
more pressure making it increasingly difficult for the
world to meet the 2010 target—to reduce the rate
of loss of biodiversity by 2010”.
“Migratory species are in many ways more vulnerable
as they use multiple habitats and sites and a wide suite
of resources throughout their migratory cycle. So we need
to bolster rather than clear habitats, reduce pollution
to the land, freshwater and the marine environment, more
sustainably manage water supplies for people and wildlife
and enact other measures to assist animals and plants
to cope and to adapt in a climatically changed world,”
UNEP and CMS argue that conserving and more sustainably
managing biodiversity in a climatically- changed world,
is of the highest economic importance and important in
the fight against poverty.
“Take the host of the climate convention talks,
Kenya. Its national parks and biodiversity generated $700
million in foreign exchange from tourism last year. If
its parks and its biodiversity—from elephants to
lions and rhino to wildebeest—were lost as a result
of climate change, the impacts will be felt by the economy
and the livelihoods of local people who depend on visitor
income,” said Mr Steiner.
Robert Hepworth, Executive Secretary of UNEP CMS, said:
“The best form of adaptation is mitigation-in other
words reducing greenhouse gas emissions by the 60 per
cent to 80 per cent that is likely to be needed to stabilize
the atmosphere. But we know that the world can no longer
avoid some measure of climate change now and in the future,
so we must act to help people and the wildlife, upon which
many livelihoods depend, adapt”.
Sigmar Gabriel, the German Environment Minister from the
country hosting UNEP-CMS, added: “I also fully endorse
the new report’s conclusions. Measures, such as
maintaining a coherent network of stop over sites like
wetlands; creating and expanding suitable habitat like
field margins, hedgerows and ponds and developing and
sustaining trans-boundary corridors that allow species
to migrate as the climate changes, will be key to ensuring
a healthy level of biodiversity now and in the future,
“ he added.
Highlights from Migratory
Species and Climate Change: Impacts of a Changing Environment
on Wild Animals
Changes in Migration Routes and Barriers to Migration
Changes in the length, timing and location of migration
routes are being documented. In extreme cases, species
have abandoned migration altogether. In other cases, species
now migrate to areas where they have not been recorded
other than as occasional vagrants.
· Exotic southern fish species like the Red Mullet,
Anchovy, Sardine and Poor Cod are now being found in the
North Sea. Fish species are ectotherimic (unable to regulate
their body temperature) and their distribution and abundance
are temperature dependent.
· European Bee-Eaters (Merops apiaster) once very
rare in Germany are now breeding regularly across the
· The Rosy-Breasted Trumpeter Finch (Rhodopechys
githaginea) is one of many birds once normally confined
to arid North Africa and the Middle East now found in
increasingly large numbers in southern Spain.
· The arrival of hundreds of Bewick Swans (Cygnus
columbianus) flying in distinctive “V” formations
used to herald the arrival of the British winter; ornithologists
now report numbers down to double figures. Warmer weather
on the continent and the absence of the NE winds which
aid their migration are the likely reasons for the swans’
non-appearance in their traditional British wintering
· Changing wind patterns are making it more difficult
for passerine birds to make their migration in the Caribbean
where spring storms are becoming more numerous and of
· This autumn several large Monarch Butterflies
(Danaus plexippus), which migrate in millions every year
from the USA and Canada to Mexico, have been blown across
the Atlantic to England 5000 km away.
· Desertification increasing the size of the Sahara
Desert will adversely affect the ability of Afro-European
migrants to cross this ecological barrier successfully
The following changes are being witnessed:
· the permafrost is thawing and Arctic tundra is
being replaced by forest; · desertification is
occurring in Africa;
· sea levels are rising;
· hurricanes are more frequent in the Caribbean;
· Antarctic waters are getting warmer and the ice
is melting affecting sea salinity
Spatial distributions are changing – one study showed
the range of certain taxa has moved on average by 6.1
km towards the poles and 1m in elevation in the space
of a decade. Arctic-alpine specialists will face greater
competition for habitat from other species which did not
previously occur at higher altitudes and latitudes.
Alien species like the Pacific Oyster (Crassostrea gigas)
brought to Europe for commercial reasons used not to be
able to survive outside artificial pens. As the North
Sea has grown warmer, the Pacific oyster has been able
to breed in the wild and is now displacing native oysters
in the Wadden Sea.
Incidence of flooding and resultant sediment run-off in
Queensland, Australia damaged seagrass pasture leading
to reduced growth and breeding rates for Green turtles
Baffin Bay hosts the largest concentrations of wintering
Narwhals (Monodon monocerus). Here the trend has been
for increased ice coverage in winter. The Narwhals depend
on cracks in the ice to breathe and there have been several
occasions when they have become trapped in the ice. Their
site fidelity and the decrease in open water make them
susceptible to Climate Change.
There is likely to be a general shift of species towards
the poles, reducing the range of species most adapted
to colder waters. The Common Dolphin (Delphinus delphis),
a warm water species is increasing its range, while the
White-beaked Dolphin’s (Lagenorhynchus albirostris)
range is reducing. Predators are following their prey
as prey species (eg fish) change their mean latitude and/or
As migratory species are affected by climate change, then
so are their prey species. For example, reproductive success
of the non-migratory Great Tit (Parus major) and migratory
Pied Flycatcher (Ficedula hypoleuca) is being affected
by the changing availability of caterpillar food supplies.
The temporal mismatch of prey and predator is part of
a phenomenon known as “phenological disjunction”.
Reduced oceanic salinity causes shifts in the distribution
of biomass constituents of the food chain with a tendency
for poleward shifts in species assemblages and the potential
loss of some polar specialist species like the Narwhal
It is doubtful whether Polar Bears (Ursus maritimus) will
be able to adapt fast enough to changing ice conditions
affecting the habitat of their seal prey species, and
the disappearance of the ice threatens the bears’
Predator demographics are affected by prey. Market Squid
(Loloigo opalescens) left southern California followed
by the Short-Finned Pilot Whales (Globicephala macrorhynchus)
which prey upon them. When the squid returned Risso’s
Dolphins (Grampus griseus) filled the gap left by the
whales; Bottle-nosed Dolphin (Tursiops truncatus) numbers
rose at the same time but did not decline again after
the end of the El Niño event.
Krill may be outcompeted by other species more tolerant
of warmer water with repercussions for species higher
up the food chain, including penguins, albatrosses, seals
and cetaceans, despite their wide foraging ranges.
Animals and plants specialised to live in Arctic and Alpine
environments will also face greater competition for food
from other species which did not previously inhabit higher
Data gleaned from strandings show that changes in Sperm
Whale (Physeter macrocephalus) distribution in the NE
Atlantic can be attributed to shifts in the North Atlantic
Oscillation and to the knock-on effects on the squid species
upon which they prey.
Abundance and quality of prey species is important, especially
in stopover sites, and most particularly in stop-over
sites adjacent to large barriers such as the Sahara Desert.
Severe breeding failures affected important seabird colonies
in Scotland as a result of warmer waters leading to a
loss of plankton and reduced fish numbers. In some cases
100% breeding failure occurred in some years. Following
the Sahel drought of 1968-69 Whitethroat Warbler (Sylvia
communis) numbers are still only 25% of what they once
Reduced breeding success (probably prey related) is apparent
in some Antarctic species. In birds, abnormally heavy
rainfall can adversely affect mortality rates among fledglings.
The El Niño Southern Oscillation in 1982 is thought
to have resulted in the loss of an entire year of Galapagos
Fur Seal (Arctocephalus galapagoensis) pups and abnormally
high mortality rates among juvenile seabirds.
The El Niño Southern Oscillation will also have
impacts on Green turtle (Chelonia mydas) breeding migrations,
and rising sea levels may lead to the loss of turtles’
Cues in the wintering grounds that it is time to migrate
may no longer be a good measure of conditions in the breeding
grounds (another example of the phenomenon of “phenological
Bats have been known to arouse from hibernation early
affecting the females’ reproductive cycle.
Reduction of sea ice will impact on Ringed Seal (Pusa
hispida), Bearded Seal (Erignathus barbatus) and Walrus
(Odobenus rosmarus) populations that use ice floes for
resting, moulting and giving birth.
As mentioned above, the Lesser White-fronted Goose (Anser
erythropus) is a particularly vulnerable species being
reliant on a small number of discrete stopover sites.
Incidence of Disease
Fibromapilloma tumours in Green turtles (Chelonia mydas)
are thought to grow faster in warmer waters and their
prevalence has increased since the 1980s. Other diseases
and parasites thrive in higher temperatures and will impact
more profoundly on the populations of their victim/host
Global warming may engender algal blooms and contribute
to epizootics. Mass die-offs of marine mammals have increased,
and where the cause has been viral, environmental factors
have contributed to the outbreaks or reduced the ability
of the animals to fend off the illnesses.
Reduced food supplies for Cetaceans in warmer waters affect
the condition of females and interfere with the frequency
of their reproductive cycles.
Reduced rainfall in the eastern Mediterranean caused a
drop in nutritional levels in the sea affecting the health
and condition of Striped Dolphins (Stenella coerulealba).
Feminisation of Populations
The sex ratio of turtle hatchlings is temperature dependent
in both the Dermochelyidae and Chelonidae families. Higher
temperatures in the range 25-32OC lead to greater number
of female young (and lower temperatures to more males).
An imbalance of 1 male:2 females or 1:3 has no ill-effect
but if the proportions move towards 1:4, populations may
be adversely affected. Some nesting beaches are seeing
temperatures rise above 34 OC which is often lethal.
Notes to Editors
Migratory Species and Climate Change: Impacts of a Changing
Environment on Wild Animals by UNEPCMS is available at
UNEP’s resources on climate change are at www.unep.org
For More Information Please Contact
Nick Nuttall, UNEP Spokesperson, on Tel: +254 20 7623084,
Mobile: +254 733 632755, E-mail: firstname.lastname@example.org;
Paola Deda, Inter-Agency Liaison Officer, UNEP/CMS Secretariat
at the UN Premises in Bonn, Hermann-Ehlers-Straße 10,
53113 Bonn, Germany: telephone (+49 228) 815 2462; fax
(+49 228) 815 2449; E-mail: email@example.com