As regular CFZ-watchers will know, for some time Corinna has been doing a column for Animals & Men and a regular segment on On The Track... particularly about out-of-place birds and rare vagrants. There seem to be more and more bird stories from all over the world hitting the news these days so, to make room for them all - and to give them all equal and worthy coverage - she has set up this new blog to cover all things feathery and Fortean.

Thursday, 19 March 2015

Mercury pollution poses threat to Arctic birds

By Tim Sandle 16 hours ago in Environment
Research indicates that mercury pollution has risen around 50-fold in the feathers of a rare Arctic bird over the past 130 years. Conservationists are concerned for the bird’s future.

The bird at risk is the ivory gull. The ivory gull (Pagophila eburnea) is a small gull (17 inches tall) which breeds in the high Arctic. In non-breeding seasons the bird can be found in Greenland, Canada, and Eurasia. Unusually for a gull, the bird has a totally white plumage.

There are around 20,000 birds in existence. The species is said, by the International Union for Conservation of Nature, to be in rapid decline and the status is “threatened.”

As well as habitat loss and risk from predators, the ivory gull has a new threat: mercury poisoning. New research, based on a review of museum specimens, indicates high mercury levels in the gulls. The analysis spanned the time period from 1877 to 2007. Here the increase in mercury levels was over fifty times, with the greatest rises occurring over the past thirty years.

The finding with the gulls is consistent with rising mercury levels in other Arctic birds, fish and mammals. The source of the mercury probably relates to atmospheric pollution. The gull is a good indicator of mercury levels due to the absorption of the toxin into its feathers. The direct concern with the gulls is that, in time, this will affect the bird’s reproduction.

No comments:

Post a Comment