If you click on any images in the blog, it will be opened in a separate window, will be larger and it will be easier to see detail.

Blog posts after 1 Feb 2018 about Steppe eagles tracked from Oman can be found at the Steppe eagle blog

Wednesday, December 23, 2015

More about electrocution

Worldwide electrocution is a huge problem for large birds, including many eagles and vultures. Many of the species affected by electrocution (like the Egyptian vulture) are also endangered, and electrocution contributes to their poor conservation status.  Click here to access a paper on electrocution of Egyptian vultures in East Africa by Ivaylo Angelov and others.  If you Google the words "bird electrocution power lines" you will be able to see loads of images of many species that have been electrocuted, mostly large species and many predatory birds

Oman is recognized as a global stronghold for Egyptian vulture because of its seemingly stable breeding population, and as a destination for many migrants from farther north.  It is also an important winter destination for migrating eagles, like the endangered Steppe Eagle (which is on the 100 Baiza note) and Eastern Imperial Eagle.  Oman was thought to be relatively safe for Egyptian vultures, and other species, although the possibility that birds were being electrocuted was always there.  Sadly, this incident shows that electrocutions occur, we just don't know at what rate.
Juvenile Egyptian vulture perched on a dangerous power line in Oman. (Photo: A. Kovac)

While the news of this bird's death is sad, and the prospect that more birds are electrocuted is worrying, there is a positive side.

1) Oman is a developing country and is only now installing much of its power transmission network, a process that will grow as the human population grows and human activities are started up in new areas.  This means that using pylon designs that reduce electrocution during this development phase could help avoid future electrocution at almost no additional cost.  Much has been done in North America http://www.aplic.org/, Europe and Africa to design such safe pylons.

Juvenile golden eagle electrocuted on a power line in North America (Photo: USFWS)
2) The distribution in Oman of the large birds that are most vulnerable to electrocution is somewhat predictable.  Many of the migrating raptors are also scavengers and concentrate near rubbish dumps and many of the resident raptors are territorial and use particular habitats.  This means that "sensitivity maps" can be drawn that identify areas where risk is particularly high, and these areas can then be the focus of efforts to reduce that risk.  In doing this the biggest conservation benefit will be realized sooner and with the least effort and cost.

Wintering Steppe Eagles on a dangerous pylon near a rubbish dump in Oman (Photo: A. Kovac)
3) In some cases the most immediate solution is to change the pylons that are most dangerous.  This, of course, costs money.  Because of this problem bird biologists have long worked with transmission line engineers to design cost-effective solutions or retro-fitting.  Indeed, in the long run these modifications could save money by reducing the number of times engineers have to visit sites of electrocution.  Reducing electrocutions would also have the advantage of reducing power outages to customers.

If you'd like to read more about this problem, click on the links below.


No comments:

Post a Comment