Cleanings

Regular watchers of our camera will have noticed the fog that developed over the camera window yesterday. When we cleaned the box during the bee incident, we must have cleaned it inadequately. Today, I went up to clean it. I took the opportunity to check on the owlets, and only one of them now has an eye swollen shut. So, they're on the mend.


I also did a bit of research on the No Pest Strips that killed the bees. They contain a nerve agent, called dichlorvos, that the EPA has considered banning. It is a nerve agent developed around WWII, and has caused birth defects in rodent studies. It can cause lung, eye, and muscle problems, and death. The idea behind it's "safety" is that in low doses, it is much more toxic to insects than to people.

According to OSHA:
1. Effects on Animals: Dichlorvos is an anticholinesterase agent and may cause excessive salivation, eye tearing, sweating, constricted pupils, respiratory distress, anorexia, vomiting, diarrhea, weakness, twitching, paralysis, a slow and irregular heartbeat, convulsions, coma, and death [Hathaway et al. 1991]. Dichlorvos also has reproductive effects and causes malformed offspring in rodents. The acute toxicity of dichlorvos for laboratory animals is significantly high; the dermal LD(50) for rabbits is 107 mg/kg and 80 mg/kg in rats; and the acute oral LD(50) in rats is 25 mg/kg [NIOSH 1995; ACGIH 1991; Sax and Lewis 1989]....
2. Effects on Humans: Dichlorvos is an organophosphorus pesticide and is therefore a cholinesterase inhibitor. Overexposure to this substance causes symptoms that vary by route of exposure. Inhalation causes ocular and respiratory symptoms. Ingestion causes gastrointestinal effects, while skin absorption causes localized sweating and muscle twitching in the area where entry occurred. If exposure is severe, muscle weakness, twitching, fasciculation, and paralysis may occur. Paralysis of the respiratory muscles may cause death. Cardiac irregularities, including complete heart block, may also occur [Hathaway et al. 1991]. Dichlorvos is easily absorbed through the skin, gastrointestinal tract, and lungs because of its high volatility [Parmeggiani 1983].

And according to the New Zealand Environmental Risk Management Authority:

Dichlorvos is also very ecotoxic to aquatic organisms, birds and honeybees.

We decided that as small and fast-growing as the owlets are, it could definitely cause them some problems, so I took down one of the strips in the morning. With no additional bees by 2pm, we knocked down the other strip, and have left them toxic-free.