Godwit in flight, pwallace 2009
In 2008 Birdlife International updated its comprehensive assessment State of the world’s birds. The report documents a global situation with some notable conservation successes, but generally characterised by continuing species extinction. It records thata total of 153 bird species is believed to have become extinct since 1500 AD, with 18 species lost in the last quarter of the twentieth century and three more known or suspected to have gone extinct since 2000. It is assessed that 1,226 species (one in eight of the total) were considered threatened with extinction. (BirdLife International State of the world’s birds 2008: indicators for our changing world (United Kingdom: BirdLife International, 2008). http://www.birdlife.org/worldwide/index.html
Red knot pwallace 2009
Red Knots, also known as lesser knots or Huahou, breed in widely separated parts of the high Arctic and winter in temperate and tropical estuaries of both Hemispheres (Heather & Robertson 2005). There are about 6 sub-species and they disperse to different areas across the globe. Red knots have been making headlines in conservation news as important parts of their habitat have been eroded by commercial fisheries and other development. The birds generally feed on hard-shelled molluscs and crustaceans. Due to a strong gizzard they are capable of swallowing shells whole. Unfortunately humans are also very partial to the same foods and a competition has emerged, with the birds coming off decidedly second best. The Wadden Sea in the Netherlands has offered prime habitat for knots due to the ready supply of molluscs. However due to intensive commercial shellfish dredging the site now produces slim pickings and bird numbers have plummeted. A similar story is told at Delaware Bay, on the North Eastern seaboard of the United States. Red knots had once thronged there on migration stopover, drawn by juicy abundant supplies of the eggs of spawning horseshoe crabs. However, human demands for the crab (largely as fish bait) dramatically impacted the birds’ ability to refuel and likely contributed to a large decline in annual survival of the species. (For full details see Piersma, T “Migration in the balance: tight ecological margins and the changing fortunes of shorebird populations” in Boere, GC Galbraith, CA & Stroud, DA (eds) Waterbirds around the World (The Stationery Office: United Kingdom, 2006) 74.
Godwit weigh-in pwallace 2009
The sub-species of red knot which makes its way to New Zealand shores, arrives in September-October having made its way in 4 or 5 flights down through eastern Asia and Australia or Irian Jaya. This migration route is of considerable concern to those monitoring the birds as stop-over sites are vital in terms of refuelling for the long journey home. Incompatible development activities in these areas could have consequences for the species, as in the Netherlands and the United States. Members of the Wader Study Group and the Miranda Shorebird Centre have been active in making monitoring visits to the Yellow Sea to examine staging posts and make representations to Governments regarding the activities occurring there. In addition the migration route raises the possibility of the contraction and spread of avian influenza.
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