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Illegal Cannabis Farms Are Poisoning Endangered Birds

Scientists in California have been testing endangered owls as there have been concerns over the impact of toxic pesticides and other chemicals. They found that a disturbing 70 per cent of northern spotted owls, an endangered species, and 40 per cent of barred owls had been exposed to rodenticides. In other words, rat poison.

Illegal Farming in California

It is believed that illegal cannabis farms are the most likely source of the poison. California has legalised cannabis for recreational use and there are now up to 50,000 marijuana farms in the state. However, only around 16,000 of the farmers are expected to apply for licences to grow their crops legally. California accounts for over 90 per cent of all illegal cannabis farming in the US.

Banned Fertilisers and Pesticides

There are few incentives for farmers to grow legally and most dislike taxes and red tape. No surprise there then! To make matters worse, it is anticipated that illegal cannabis farming will increase now that recreational use has been legalised. The illegal growers use fertilsers and pesticides which have been banned for many years in the US, including carbofuran.

Insufficient Monitoring

The recent testing of the owls was part of a study led by Dr Mourad Gabriel, an expert on cannabis contamination issues from the University of California, Davis. He stated in his report that there are insufficient measures in place to monitor the activities of the illegal farmers. Forested areas are being converted into cannabis farms and these are the natural habitats of the endangered owls.

Impacting Natural Habitats

The farms are encroaching on owl habitats and are also creating clearings which make it easier for the birds to hunt their prey, prey which may have eaten the toxic chemicals. Owls tend to feed at the edges of the forest and the farms now form those edges. Toxic chemicals leach into the surrounding environment and so impact all wildlife.

"If no one is investigating the level at which private marijuana cultivators are placing chemicals out there, the fragmented forest landscapes created by these sites can serve as source points of exposure for owls and other wildlife," said Dr Gabriel.

Lethal and Non-Lethal Consequences of Toxins

There has been very little research into the non-lethal effects of the rat poison on owls. But it is known that it causes a decrease in the size of the chicks and the reduces the number of eggs being laid. There is also an increase in mortality rates following injury. The owls tested were all dead and had been found dead and collected in the wild. The scientists say that they are valuable evidence of the damage being done and are calling for increased monitoring of farming activities before it is too late for the birds.


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