Dutch scientists have placed satellite tracking devices into the abdomens of 15 Black-tailed Godwits (Limosa limosa) to find out where and when these birds move. Some interesting data has already been collected. One of the birds left Friesland (in Holland) on Saturday and was in Senegal (West Africa) just two days later! That’s over 4000 kilometres (Spain, Mediterranean and Sahara desert) in just 48 hours. Amazing! Here’s more from Science Daily:
Since last week, 15 black-tailed godwits in Fryslân (in the north of the Netherlands) have been flying around with tiny transmitters in their abdominal cavities. The transmitters were inserted during a minor operation by the American vet Daniel Mulcahy and his Dutch colleague David Tijssen. With the help of the transmitters, researchers will be able to track the birds for about a year in their breeding grounds in Fryslân as well as during their migration from and to Southern Europe and Africa. [more here]
The North American subspecies of Red Knot (Calidris canutus rufa) is in trouble. Although Red Knot is globally a widespread species, this particular subspecies has declined dramatically because of past hunting activities and more recently competition for food in Delaware Bay.
Each year Red Knots stop over at Delaware Bay to feed on Horseshoe Crab eggs, but these birds competed directly for this food source with crab harvesters. This stop-off area is a critical point in their migration from South America to the Arctic where they breed. Birds arrive at Delaware Bay with almost no food reserves and after a few weeks of almost continuous feeding their fat levels are replenished and they’re ready to complete the final leg of the migration. Without sufficient reserves a lot of these departing birds perish en route to their breeding grounds.
Wiki provides a good overview of the various Red Knot subspecies, of which there are six.
Reports from researchers this year indicate that this subspecies may have turned the corner; their numbers appear to be on the rise. Here’s more from Philly.com:
Once numbering nearly 100,000 on the bay, the birds have declined to about 15,000. Biologists blame a reduction in the number of crabs, which were heavily harvested through the 1990s. Gradually, in what officials said was the first time a species not in trouble was regulated to help another that was, crab harvest restrictions have been enacted. Still, neither the crabs nor the birds have shown a comeback. Biologists fear the red knots could plummet into extinction with an event as simple as a summer snowstorm in the Arctic or an oil spill in South America. Advocates have repeatedly, but unsuccessfully, tried to get the U.S. Fish and Wildlife Service to designate the bird – a subspecies called Calidris canutus rufa – as federally threatened or endangered. Yesterday, the researchers packed up and headed home after spending a month on the bay capturing red knots with sophisticated netting devices. They logged biologic data and banded the birds before setting them free. Australian shorebird expert Clive Minton, who has joined Niles on the bay since 1997, called it “an exciting year. We think we’re really seeing the beginning of a possible turn-round in the fortunes of the crabs and the shorebirds.” [more here]
We reported on the shooting of two California Condors here, but the hunting of birds is a global problem. Each year thousands of migratory species are gunned down in north Africa and Europe as they pass through traditional flyways. Many trigger-happy nations are responsible for this massacre, but the Mediterranean island of Malta is one of the main culprits. To give you an idea, of a population of 400, 000 people as many as 16, 000 are registered hunters. Harriers, eagles, kites, herons, osprey and many passerine species use Malta as a resting point when crossing the Mediterranean between Africa and Europe each spring and autumn. When these birds arrive they are gunned down by waiting hunters. What makes the situation worse is that in spring these birds haven’t had a chance to breed yet, so not only are we losing individual adults, but also the offspring they would have produced.
Birdlife International in collaboration with Birdlife Malta are working hard to get the situation under control. Each year volunteer camps are arranged for birders to patrol the island and monitor what hunters are up to. What makes the situation difficult is that as per the European Union Bird Directive, all hunting is banned in spring and autumn, but Malta has allowed the shooting of European Turtle-dove and Common Quail to continue so hunting still occurs at this time. This spring it was reported that over 950 shots were recorded by volunteer groups and endangered species are still being targeted. This from Birdwatch:
Spring Watch have noticed poachers targeting roosting birds late in the night, from behind high walls while observers with binoculars tipped them off by radio. They have even been observed using muffled shotguns. 52 birdwatchers from eight countries, together with nine local team leaders, are taking part in this year’s Spring Watch Camp. So far 96 different species of migratory birds, including 11 raptor species, have been observed. British birder, Gerry Keyworth, who has taken part in Spring Watch twice before, commented: “These people are not hunters, as they did not pursue the birds; they are slaughterers. It is very upsetting, particularly seeing that the bigger, more colourful birds are mostly targeted”. [more here]
It was World Bird Migration Day this weekend. A key drive of this event was to highlight the increasing impact that wind farms, buildings, power lines and other human structures are having on migratory species. The event was widely supported with countries around the globe hosting local migration day awareness drives. Take a look at their website; let’s hope the world-wide support will help catalyze this initiative: World Bird Migration Day.
There is little dispute that badly planned wind farms can have a catastrophic impact on resident and migratory bird species. The move towards renewable forms of energy like wind farming is a good one, however turbines must not be placed in areas where bird strikes are likely to occur.
A poorly positioned wind farm in Norway has practically wiped out a population of White-tailed Sea-eagles. This from the BBC:
The RSPB says nine white-tailed eagles have been killed on the Smola islands off the Norwegian coast in 10 months, including all of last year’s chicks. Chick numbers at the species’ former stronghold have plummeted since the wind farm was built, with breeding pairs at the site down from 19 to one. Scientists fear wind farms planned elsewhere could also harm birds.