Note: There are a couple of rather graphic pictures in this post. Audio included at the end.
Losing an animal to any sort of predation can be incredibly difficult to stomach, and a lot of times completely unexpected. The scenes we typically imagine in the wild are those of peace, where cattle low, birds sing, and big, blue skies give way to far-away horizons.
Windmill, 100% clear blue sky, ravens aloft, cattle grazing..GREAT long run this morning! pic.twitter.com/OCR5EA2A
— Beth Nobles (@trailgirl) October 14, 2012
But, that isn’t always the case.Imagine looking into the picture above and seeing a newborn calf ambushed by ravens. For many ranchers, this isn’t something to imagine — they’ve seen it for themselves.
In light of interest and conversation around raven predation, we’ve been doing a whole lot of emailing with livestock specialists across Canada, and raven kills aren’t as uncommon as you would suspect, though it can be incredibly difficult to determine whether or not an animal is being scavenged, or died as a result of its wounds.
Signs of Raven Predation
Ravens present a unique challenge because they often attack animals that are not moving or have moved little (particularly newborns), making it difficult to tell whether the death was due to predation or other factors that preceded feeding. Some of the general signs we can assess include looking for bleeding around wound sites, and looking for haemorrhaging on interior tissues during post-mortem that correspond with wound marks on the carcass. Both of those signs indicate the animal was alive when feeding occurred, whether or not the feeding was the primary cause of death.
Preventing livestock attack from ravens is by far the best tactic, for a few reasons. First, and perhaps foremost, is that most of the best management practices that deter ravens also deter other predators and scavengers, lessening the costs to producer time, government programs and animal welfare. The second reason to prevent (as opposed to react to) scavenging is that wildlife have a special place in the environment, and preventing conflict respects their place (off farm, scavenging other animals). And thirdly, if ravens don’t get a taste of livestock, they just might not see them as food.
called an unkindness.
“With coyotes, we know if we remove the problem coyote which has a taste for sheep, sheep can co-exist with coyotes for years without any attacks. With ravens, I believe the same thing exists. We have a lot of Ravens which are around our cattle. They come down and take hair off the cows back in the spring to build their nests. So far we have not had a problem with them attacking calves.”
This leads us to the one of the many prevention tactics we’ve found in our reading: properly — and immediately — burying or composting deadstock.
Best Management Practices for Preventing Raven Attacks
- Record Keeping & Monitoring – Beyond sending the signal that there is a human presence to potential predators/scavengers, any information of attacks may help us understand which pastures and/or times show increased threats to our animals. In reacting to problems this information can also help in applications for compensation.
- Protected Birthing Area – If possible, setting aside a birthing area that is not bordering prime wildlife habitat could discourage predators from exploring the herd/flock’s station. Birthing area that is protected versus an exposed area or an area bordering prime wildlife habitat
- Appropriate Dead Stock Management – As mentioned above, there is some belief that predators may not recognize livestock as food until they taste it. Improper burial/disposal will also act as a lure to groups of scavengers, who act as a signal to hungry predators as well. Check out Beef Research School: Dealing with Deadstock — Your Options, Plus Tips for Effective Composting
- Proper Management of Ill or Injured Calves – Keeping ill or injured calves away from that aforementioned prime wildlife habitat can help prevent easy take-downs. Related: The Importance of Segregating Ill or Injured Animals
- Other Ideas – We spoke to quite a few beef specialists across western Canada, and most agreed that ravens are simply too smart to change to be deterred by the presence of livestock guardian animals, with little evidence to suggest otherwise.
Compensation programs vary by province. Livestock in Alberta and Manitoba are not eligible for compensation covering raven kills, where Ontario and Saskatchewan are. Like all wildlife claims, there must be sufficient evidence to prove the death was caused by a predator attack.
Saskatchewan Crop Insurance Corporation’s Dan Baber talks about the frequency of raven predation in the province, signs/symptoms of a raven attack, prevention and control.