Red Kite Chicks fall Victim to Rodenticide Use!

Red kite chicks fall victim to irresponsible rodenticide use

James Reynolds
Head of Media

An RSPB officer involved in monitoring the reintroduced population of red kites on the Black Isle believes that adult birds have been feeding their growing chicks with carcasses of pest animals that have been poisoned on local farmland, with catastrophic consequences.

Brian Etheridge, RSPB Red Kite Officer for North Scotland, has been monitoring the situation over the past 15 years. This summer, he visited three separate nests on the Black Isle and discovered eight chicks in total either dead or dying following ingestion of rodent carcasses contaminated with rat poison. “These young birds were displaying classic symptoms of rodenticide poisoning, a particularly painful way for any animal to die,” commented Brian. “Many rodenticides contain anticoagulants, which gather in the liver of an animal causing heavy internal bleeding. Young red kite chicks undergo a particularly fast growing phase and require a rapid circulatory system in order to grow healthily. Anything that interferes with the blood supply of a young kite is of serious concern and sadly, in every instance, these rodenticides have proven fatal to them. These eight chicks were all quite big, and very close to leaving the nest, but the real number of chicks affected may be more than this. Chicks which die from rodenticides when very small may be removed from the nest by the adults and the cause of nest failure will be never be known. This incident is devastating for the Black Isle red kite population as these eight chicks represent nearly ten per cent of the total red kite chicks produced there this year. ”

There is a legitimate need for rat populations to be controlled in many areas particularly around farm buildings and other rural sites. The most commonly used method is the laying of baits containing poisons, known as rodenticides.

Kites are predominantly scavengers, meaning they like to scour the countryside for dead animals to feed upon and as such are admired by ecologists for their role in cleaning up the environment. This lifestyle can unfortunately make them vulnerable to the use of poisons in our countryside as their keen eye-sights very quickly pick out dead carcasses from great heights. Sadly, this includes animals which have been poisoned, requiring vigilance on behalf of people who use rodenticides on their property.

“People can prevent the unnecessary deaths of an already rare and vulnerable species as well as injury and death of other wildlife including their own pets by seeking appropriate ways to control rodent infestation,” Brian continued. “To that end, the RSPB has produced an information leaflet on how to effectively control rodent infestation in a responsible way. This leaflet contains impartial advice and best practice guidelines, such as searching for and correct disposal of dead and dying rats. It also recommends that farmers who regularly see kites foraging around their fields and farm buildings should be particularly cautious when using rodenticides, particularly in the summer months. I would really encourage everyone to have a read of it to get all the appropriate information on the subject prior to choosing rodenticides as a control option.”

“There is no doubt in my mind that these latest poisoning cases are just tragic accidents but by making informed choices about pest control, we will be able to reduce rat numbers effectively as well as preventing unnecessary damage to our local wildlife”.

The free leaflet entitled ‘Rat poison and the threat to wildlife’ may be obtained by contacting the RSPB on 01463 715000.
Notes

1. The Black Isle was the location of the first red kite reintroduction programme in Scotland starting in 1989, and yet the population growth and range expansion of red kites in this area, since initial releases, has been far lower in comparison to other release areas across Scotland and the other parts of the United Kingdom.
2. This population is already under serious threat from the impact of deliberate and illegal killings. A scientific paper comparing the fortunes of the Black Isle population with an equivalent population in England was published earlier this year. The paper is authored and titled: Smart, J., Amar, A., Sim, I,M.W., Etheridge, B., Cameron, D., Christie, G. & Wilson, J.D. 2010. Illegal killing slows population recovery of a re-introduced raptor of high conservation concern – The red kite Milvus milvus. Biological Conservation. DOI: 10.1016/j.biocons.2010.03.002. The website for this journal is: www.elsevier.com/locate/biocon

3. Red kites are primarily scavengers, eating mainly dead rabbits, birds etc and do not regularly take live prey, posing no threat to game or farming interests. Red kites are physically incapable of catching and killing prey larger than a medium sized rabbit.

4. Anticoagulants work by inhibiting the generation of vitamin K. When vitamin K cannot be generated, clotting factors cannot be activated, producing internal bleeding in the animal resulting in death.

5. The RSPB recognises the need for pest control in rural and urban areas but advocates a responsible attitude to pest control.
6. All the red kite chicks were found bleeding from the beak and from the base of their feathers, resulting from internal bleeding.