Did you mean “coywolf”?
Coydog is totally distinct from eastern coyotes, and typically denotes a recent F1 or F2 hybridization of coyote and dog.
Eastern coyotes are a distinct subspecies of coyote that mostly occupies the north-eastern range of the US - with significant genetic admixture over the last several hundred years. They are not true “hybrids” – they are a whole different subspecies.
From a genetic standpoint they are typically 50-70% coyote with dog and wolf ancestry, but are not F1 or even F2 hybrids – similar to how WBs of today might be 30% TB but the last purebred TB in their pedigree was ten generations ago. This type of admixture is not rare in canids: wolf subspecies have anywhere from 10-60% coyote admixture depending on subspecies. Their breeding cycles coincide and both species have had significant overlap genetically.
Eastern coyotes are only slightly larger than their western cousins. They average 50-70lb, whereas western coyotes average 25-45lb. They are typically medium-dog sized with larger “rust” areas, a darker dorsal, and a more robust skull than western coyotes. In the NE where I am, they typically travel in mated pairs, occasionally with a cohort (sibling or offspring from last year). They tend to fill the same ecological niche as coyotes, primarily focusing on rodents, roadkill, and small game. They do not pose threats to large livestock but have been known to eat chicken and small livestock like newborn lambs.
If you are seeing 100lb coyotes, they are likely wolves or a very large F1 dog cross – 100lb is rare, even for a wolf. The average is 80lb for North American wolf species.
Coydogs are much more of a threat to humans and/or livestock. They often have little fear of humans or human settlements, and harass and attack livestock rather than hunt opportunistically. There were several of them for years here and they were recognizable by high white legs/socks and curled tail. They were medium sized and barked while they were harassing livestock - another thing coyotes don’t do.
