Sunday, 11 February 2024

Coyotes, Jackals and Foxes -Similar Health Issues?







I sent out emails to coyote and jackal projects as follows:

 Hello.

My name is Terry Hooper-Scharf and I a naturalist specialising in wild canids, felids and some mustelids. I set up the British Fox and Canid Study in 1976 and over the last two years we have managed to get (fight for) official examinations of non-road kill foxes. Obviously motor vehicles kill wolves, coyotes as well as other animals and just in the City of Bristol for 2023 we recorded 257 fox deaths due to cars.

One thing our Fox Deaths Project has shown through post mortem examinations is that foxes look externally unmarked and all of the damage is internal which led to many claims that someone was poisoning the foxes. What our pathologist has found during post mortem examination is a prevalence of worms such as heart and lung worms as well as Uraemia/kidney problems/verminous pneumonia with prey likely the sources.

What I am interested in finding out is whether any post mortems on jackals from Austria have shown that they are similarly affected -or whether you know of such findings from other jackal projects?

If interested I can forward a couple of the post mortem reports to show what has been found?

I look forward to hearing from you when convenient.

Regards

Terry

The Edmonton Coyote project responded first and noted that:

 "Some previous research in our lab has examined coyote health, and past projects have included necropsies on coyote carcasses collected in and around Edmonton, Alberta. 

"As far as I know, the majority of the carcasses examined were either lethally managed (for population control in rural areas, or to remove conflict-prone coyotes) or were roadkill found within Edmonton. As part of the necropsies done on these coyotes, their spleens were measured to assess immune function and their intestines were examined for the presence of parasites, particularly the tapeworm Echinococcus multilocularis

"I do not believe this tapeworm tends to kill coyotes, but coyotes (as well as foxes and other canids) become infected by eating infected rodents. It was found that, overall, urban coyotes were often more heavily infected than their rural counterparts. 

"Just three urban individuals had particularly heavy infections and accounted for >70% of the scolexes counted. Young coyotes seem to be more susceptible to infection with E. multilocularis than older coyotes, and I believe the same has been observed in foxes. I'm not sure if these patterns hold true for other parasites. "

The Atlanta Coyote Project  also responded:

"Hi Terry:

"Thanks for contacting me.  Unfortunately, I don't have much in the way of pathology reports on coyote postmortem exams.  I would be interested to know more about parasite loads in coyotes, though.  

"I will say that anecdotally we examined a live coyote a few years ago who we captured and brought into captivity.  A very interesting story about a melanistic coyote who was exhibiting hyper-social behavior.  It was featured in a documentary that we were part of in case you're interested in watching it (Urban Coyotes - it can be streamed from the Home page of our Atlanta Coyote Project website).  The point being is that this coyote was essentially parasite-free, which was surprising to us.  Obviously just one animal, though."

When it comes to jackals I sent a similar message to the Golden Jackal Project Austria and received this response:

"Dear Terry

"thank you for your interesting message,

"I have no such experience in jackals and do not know of it in other studies. I know that there are heart worms in jackals, if you want I can search the relevant literature..

"What I found in jackals, that it seems the are not as prevalent to mange as foxes.

"Let me know, also I can forward you to other Vets, maybe in Italy."

When it comes to foxes they tend to become worm-ridden as cubs through regurgitated food etc but the worm burden tends to lessen with age. Of the 50+ fox post mortem carried out verminous pneumonia (lung worm) seems a major health problem and as rodents are a common prey item and a source of worms (even noted in a dead otter where the likely originator was a rat)  I was interested to see whether this was true with coyotes. Heart worms are another problem and has been noted in Golden Jackals in Austria.

Back in 1994 mange was unknown in the City of Bristol until one subject fox moved out of the City temporarily and when it returned it had mange and from that one fox mange spread and over 1994/1995 we lost 96% of the City fox population. I think that there is a great deal we can learn about all canids and basic health problems are a start. 

Thanks to Zoe Webber I finally got up to date on my Bristol fox post mortem reports. 57 of them plus some on cubs from outside Bristol and the facial injury cases that came via Zoe.
We found leptospirosis, babesia, verminous pneumonia (lung worm), kidney problems and more. One thing we have not found (by "we" I mean the excellent senior pathologist who has been carrying out all of the PMs for us) is the "rampant in foxes" adenovirus -not seen one case yet.
It is probably that what they have taken to be adenovirus is in fact something else -a vet pronouncing adenovirus without carrying out a PM or tests is about as accurate as every one of the seven or so vets who reported that various Bristol foxes were "poisoned" -they were not and without a PM to back up such a claim all it does is raise concerns and panic.
From what I expected we would find ...well, it's been an eye opener and once the 57th PM report is completed I can get to work on writing a summary paper.
Everything we learn about fox health can only help in future as will  everything we can learn from rescues and the far from 'rare' facial injuries.
It will be interesting to hear from other coyote and jackal projects as well as wolf projects because we really do need to learn and share what data we have.

No comments:

Post a Comment