Sunday, 28 June 2009

Annus Horribilis for the Ducks

By the end of June i was hoping to report a bumper year for Ducklings on the River.

Sadly it has been a truly awful year, with carnage on a massive scale!
With around 100 having hatched to date, only 6 below the road bridge have survived so far.
The enclosed pic of the last survivor with it's incredibly brave mother is typical of the survival rate in this part of the river. I called the Mother duck brave because she has fought time and again to keep her brood safe. I have seen her fly at one of the Swans that was threatening to grab her offspring. A couple of visitors were visibly upset when they saw a black backed gull attack and take one of the last two chicks, the mother grabbed the gull by the wing and quacked furiously but the gull escaped with the chick.
I have occasionally heard that ducks are poor mothers, but on the evidence i have seen i think not.

The Balance between predators and prey has now tipped firmly in favour of the predators.

The evidence can be seen on the figures for the past few years, in 2007 out of 68 observed hatching's 32 survived the season. In 2008 about 75 hatched and 23 survived, followed by 6 survivors out of 100 this year!

As well as the ducklings, 2 adult mothers were killed by human hands, one of which was probably sitting on eggs. Another 2 mothers have damaged wings.

The Creek between the merryton and bailey bridges is now a valley of death for young ducklings. Hoodie Crows have established a nest in the spruce trees directly opposite the Swans island and have systematically targeted all ducklings in this area. The two herons have taken many chicks, so too the black back and herring gulls.

I have warned for some time about the dangers of feeding the gulls in this area, and those gulls that have successfully taken ducklings will continue to do so for years to come.

Even people feeding young black backs that stand innocently on the river path, are in effect encouraging them to came back to the area in future when they are much more deadly to other birds. We now have a colony of gulls at merryton and many people are unaware that gulls are predators and eat other small birds!

It is obvious the Duck population will decline if the predators continue killing at their present level.

When i first heard about the plan to cut down the spruce trees on the lower river, i was vehemently against it. However my gut reaction has now changed in favour of the idea.

It would deprive the hoodie crows nesting ability on this stretch of the river, in addition it would open up the river view to passers by, which in turn would keep the herons on the move at the island hotspot. Planting deciduous species, and various bushes and shrubs, like gorse, broom , honeysuckle for fragrance and colour etc, would be much more attractive and beneficial to other bird species.

The spruce trees might add a bit of contrast in the winter, but nesting for the crows is too damaging to the ducks and other species. They also killed one of the cygnets which weighed about a pound and a half at the time!

Hoodies on top of the spruce overlooking the creek. The nest is in the one on the right about 5 feet from the top.

This hoodie is a water specialist !

Having a tree as a landmark would be better placed away from the riverbank, and should also be a native species.

1 comment:

Graisg said...

Hi Joe, I've posted on the Gurn about this.