Heat waves and, in general, abnormally high temperatures have been associated in various studies with an increase in violent acts in humans. Without going any further, and in a section that is of particular concern in recent times, a study carried out in Spain whose results were published in 2018 in the journal Science of The Total Environment indicated that sexist or gender violence increases on days of waves of heat and immediately after.
Also in domestic animals, rats and monkeys in zoos, more aggressive behaviors have been observed in conditions of unusually high ambient temperatures.
A study carried out in various cities in the United States now shows, for the first time, signs of increased aggression and dog bites on humans during heat waves. Air pollution also seems to negatively affect the behavior of dogs, indicates this research, the results of which have been published in the journal Scientific Reports (of the Nature group).
The authors of the study indicate that the data analyzed show an 11% increase in dog bites to humans on hot and polluted days, but they acknowledge that the results should be contrasted with more detailed investigations in which other factors can be extrapolated. that can influence the alteration of the behavior of animals and their relationship with humans.
Previous research has documented that warmer weather and higher levels of air pollution may be associated with increased aggression in humans, rhesus monkeys, rats, and mice. However, it is not clear whether dog aggression against humans also follows this trend.
Clas Linnman and colleagues examined data on dog bites in eight US cities (Dallas, Houston, Baltimore, Baton Rouge, Chicago, Louisville, Los Angeles, and New York City) between 2009 and 2018. The data was They were drawn from publicly available repositories registered by animal control authorities or based on previous compilations of dog bites.
The record review included 69,525 reported dog bites, an average of three bites per day for ten years. The authors examined the association between dog bite rates and daily levels of fine particulate matter (PM2.5), ozone, and temperature. They also evaluated UV and precipitation levels.
The authors report that the incidence of dog bites increased by eleven percent on days with higher UV levels, by four percent on days with higher temperatures, and by three percent on days with elevated levels. of ozone. In contrast, the incidence of dog bites decreased very slightly (1%) on days with higher levels of rain. The authors reported no change in the incidence of dog bites on days with higher PM2.5 levels.
The authors note that the dog bite records did not include information on other factors that may affect a particular dog's bite risk, such as the dog's breed, sex, or whether the dog had been spayed or neutered. In addition, no information was available about previous interactions between the dog and the bite victim, such as whether the person was familiar with the dog.
The authors conclude that these findings appear to expand the association between higher temperatures and levels of air pollution and interspecies aggression to include dogs. However, more research is needed to confirm and explore this relationship.
