Inland population expansion
cormorant-breeding-change-map_1.JPG
Map showing breeding distribution changes –
showing gains in inland areas.
Click on map to see enlarged version in the BTO Mapstore.
historically, the Cormorant population in the UK and close celibate has been kept at a humble level due to persecution by humans and through reduced breeding success ( in the 1950-60s ) as a result of pesticide befoulment .
Following protective legislation against persecution in Denmark and Holland in the 1960s, the european population increased quickly and continental birds started to extend their winter image into Britain & Ireland .
Cormorants are nowadays widespread throughout Britain & Ireland with the highest densities on the slide, at estuaries and on inland waters.
Reading: Cormorant
The Cormorant population has decreased in Scotland, northeastern and southwest England. however, there has been a exorbitant increase inland in England and in regions bordering the northern separate of the Irish Sea .
- 53% range expansion since 1981-84 in Britain
- 18% range expansion in Ireland
- Population growth mainly in inland and lowland areas
- Wintering populations increased
cormorant-nest-colony-mark-collier_1.jpg
Cormorants build nests of seaweed, reed and twigs.
One of the side-effects of nesting together as a colony
is the volume of droppings, which over
time kills the breeding trees.
Cormorant now found nesting in trees
In the UK the Cormorant was about entirely a coastal breeder until 1981, when an inland tree-nesting colony became established at Abberton reservoir in Essex. This colony was later found to comprise of Cormorants of the continential sub-species, P. c. sinensis. By 2012 Cormorants have bred at 89 inland sites in England, although breeding at many of these sites was of a one nest or did not persist .
cormorant engender colonies are now wide distributed across Britain & Ireland .
Cormorants build nests of seaweed, reed and twigs.
One of the side-effects of nesting together as a colony is the volume of droppings, which over time kills the breeding trees. One of the side-effects of nesting together as a colony is the book of droppings, which over time kills the education trees .
cormorant-colony-nest-edmund-fellowes_0.jpg
Coastal birds breed within a very narrow period,
with all chicks all hatching at a similar time.
Advantages of breeding inland
research has found that the time of breeding between the inland and coastal breed birds is identical different .
coastal birds breed within a very narrow menstruation, with all chicks all hatch at a like time .
In contrast, inland Cormorants have a long breed temper. The large remainder in time of breeding within an inland colony, means that contest for food when chicks are large is reduced.
Read more : Sea Eagle
Conservation
Whilst the Cormorant population as a solid in Britain & Ireland has increased in late years, at a local floor there are some identical different trends .
Our native ( P. carbo carbo ) coastal breeding species has declined by about 11 % since 1986, with some larger declines of up to 60 % in northern Scotland .
In line, our recently established inland breeding population which is largely ( but not entirely ) associated with the continental sub-species P. c. sinensis, increased quickly following colonization, but is immediately showing signs of stabilization .
I am broadly interested in how human activities influence the ability of wildlife to persist in the modified environments that we create.
Specifically, my research investigates how the configuration and composition of landscapes influence the movement and population dynamics of forest birds. Both natural and human-derived fragmenting of habitat can influence where birds settle, how they access the resources they need to survive and reproduce, and these factors in turn affect population demographics. Most recently, I have been studying the ability of individuals to move through and utilize forested areas which have been modified through timber harvest as they seek out resources for the breeding and postfledging phases. As well I am working in collaboration with Parks Canada scientists to examine in the influence of high density moose populations on forest bird communities in Gros Morne National Park. Many of my projects are conducted in collaboration or consultation with representatives of industry and government agencies, seeking to improve the management and sustainability of natural resource extraction.