May 2011

20/05/2011

With the dotterel breeding season over we are pleased to report that 5 NZ dotterel chicks fledged compared to 1 the previous season. This increase was no doubt partly attributable to the more effective predator control. However the success rate is still very low when you consider that there are about 15 breeding pairs. And if the first clutches of 3 eggs or chicks are lost the parents will lay again up to 3 times. So potentially we should be seeing up to 45 dotterels fledged.

Christmas holiday makers at Omaha were excited when a pair of dotterels laid a clutch of 3 eggs in front of an access walkway in the middle of the beach. The Department of Conservation erected a tape barrier around the nest and in due course, in spite of the disturbance caused by passing pedestrians and dogs, the eggs hatched. Beach goers were entranced by the tiny chicks as, guided by their parents, they set out to find their first meal. Unfortunately they were gone the next morning, fallen prey to cats which were also on holiday nearby.

At high tide during the autumn the sand spit has been a bird watcher's dream. About 400 bar-tailed godwits were seen preparing for their annual migration and there are still 40 young birds wintering over here. There were over 100 NZ dotterels flocking from the surrounding coast, forming pairs for the next season, accompanied by the smaller banded dotterels which actually don't nest here. Other birds include the resident variable oystercatchers and their chicks, South Island pied oystercatchers, Caspian terns, white fronted terns, NZ fairy terns, pied stilts and wrybills.

Over the last summer we increased the number of predator traps on the spit from 12 to 26 and about 52 pests were destroyed, including rats, hedgehogs, and weasels. As the number of hedgehogs caught remained steady over autumn we decided to keep the traps out over the winter, reducing the inspections to once per week. This seems to be paying off as just this week 2 weasels were recorded. All traps will be overhauled before the next breeding season starts in August and we will be deploying an additional 5 traps.

Domestic animals also continue to be a problem with dog walkers ignoring the signs and apparently not understanding that the presence of even a well trained dog can disturb the nesting birds and lead to breeding failure. There have been signs of cats but we have been unable to trap any. Local residents are requested to keep their cats well fed and inside the house at night. Cage traps will be used on the reserve from time to time. All efforts will be made to identify owners of any cat caught in the live traps.

Finally we have observed some disturbing instances of birds injured as a result of fishing activities. The first was a black backed gull with a short length of thick nylon line protruding from its bill with a large hook on the end. This bird was photographed but we were unable to capture and assist it. The second instance was a pied shag seen flapping helpless on the beach. We were able to capture it and found it had a "soft bait" hook through its lower beak, with the nylon trace and sinkers tangled around its left wing. With some difficulty we cut and extracted the hook and cleared the line from the wing. The shag flew down the beach to the water and paddled away, hopefully a lucky survivor. The fisher having hooked the shag had just cut the line and did not consider the impact on the bird. Fishers on the spit are requested to take care not to disturb the birds and not to discard old lines, hooks or nets and not leave bait and fish parts behind which could attract rats and other predators.

Denis O'Callahan

Fundraising update

To date $94,500 of the latest estimate of $136,000 for a pest proof fence has been raised. The fence is needed to minimise predation and disturbance. It will indicate to Omaha holiday makers and visitors that the Spit is a special place requiring protection. The fence will have two pedestrian entrances with new information signage. Ideally the fence should be constructed before August 2011 which is the start of the next shorebird breeding season. If you would like to make a tax deductible donation, please click on 'How to help'.

Jill Stone

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