State of the Owl
Italian writer Marco Mastrorilli interviews Denver Holt for International Owl Awareness Day
When it comes to documenting change in the natural world, Denver Holt has seen a lot. He has studied owls in the wild for over 30 years and is one of world’s leading experts. The founder and lead researcher of the Owl Research Institute (ORI) answers questions about the research and conservation.
Q. Hello Denver, on the occasion of a world day on owls, in your opinion what are the main conservation problems these animals face? Deforestation, illegal trade ...?
A. In my opinion, as with all wildlife, habitat loss is the main conservation concern for owls. This is due to human populations and their needs for basic survival (i.e. farming, food, etc.) But also other related issues, such as resource exploitation for profit (i.e. development, logging, mining, oil and gas, poaching, etc.).
Q. Talk about the state of owls in the USA. Which species are better off? Which ones most at risk?
A. In the US, population estimates vary widely among species. Perhaps the most solid data are studies of the spotted owl. Here, numerous studies over many years, and the owls' rather sedentary nature and restricted distribution, allow for more accurate population estimates. The other species is the cactus Ferruginous Pygmy Owl along the US-Mexico border. Here, researchers have a good handle of their populations. South of the US and into Mexico they can be rather common with a wide distribution.
Several forest species seem to be stable or increasing. For example, the Saw-whet Owl, Barred Owl. For many other forest species, it is still unclear, and more research is needed.
The species to especially watch however are the open country species such as the Barn Owl, Snowy Owl, Burrowing Owl, Long-eared Owl and Short-eared Owl. Some think Barn Owls are stable or increasing while others think they are declining. The other four species have shown declines from 1970 - 2014.
However, unlike the Spotted and cactus Pygmy Owls, one has to wonder how these estimates are reached. Most surveys are not geared for owls and, with so many studies operating for such a short duration, that data could be questioned. Nonetheless, in the US we are all working from the same data base.
Q. How important and serious do you think climate change is about the future of owls?
A. Clearly climate change has been documented for 50 or so years. Hard to say how that affects and effects owls and their prey. This is all the more reason we have to get away from the short-term research methods and commit to long-term monitoring of populations on wide geographic scale, and assess annual reproduction. Easier said than done however. For example, my studies on Snowy Owls in Utqiagvik, Alaska show a population that fluctuates annually in relation to lemming population fluctuations. Although they both show high and low populations, now over 29 years, the trend is downward. And clearly in my region the climate continues to warm. My data from one region supports the downward population estimates for Snowy Owls, although who knows if they have just found better areas elsewhere.
Q. In the US there are many organizations for the protection of birds and owls. What more could be done in the USA to protect nocturnal birds of prey?