Cases of Both Mothers AND Daughters Lactating

Threesome raising a den of pups: Mom, Dad & lactating Daughter

I have now seen four cases of both an alpha female mother AND one of her remaining daughters — always a two-year-old who has just come of reproductive age — both lactating on the same territory and in the same denning area. These four cases occurred in separate families and territories. The following names won’t mean anything to most people so I’m just putting them here to differentiate them for myself. 1) Tarn (alpha female), Pink (daughter) and Rookie (new alpha male) in 2022; 2) Chert (alpha female), Squirrel (daughter), and Rookie (new alpha male in 2021); 3) Scout (alpha female), Li’lGirl (daughter), and Skipper (new alpha male) in 2023; and 4) Ma’am (alpha female), unnamed daughter, and Blue (long-time alpha male) in 2021. 

I have been attributing these “double lactations” to two different pregnancies due to the sudden disappearance of the resident alpha male and the quick appearance of a new male who moved into the vacated alpha position. This made sense to me, based on what I’ve read, that “when the alphas are killed, disorganization leads to more litters and the population increases.” [Bob Crabtree]. Indeed, the long-time alpha males totally disappeared in the case of #1, #2, and #3 above, which fit Crabtree’s conditions, but this was not the case with #4. But then again, I was only seeing the #4 family from a distance, and rarely at that, so I figured I was simply missing something from the situation.

So the obvious explanation for me was some sort of polygamy or harem situation. However, this runs in the face of what I’ve seen before over the last 17 years, and it runs counter to what we’ve been told about coyotes: that coyotes are monogamous. And also, younger females are known to be *behaviorally sterile* unless there is a disruption by killing (or a death) — and there was no disruption of this sort in family #4. So everything wasn’t aligned between what I knew and what I was seeing.

AND THEN, I read about pseudopregnancy in dogs which is apparently common phenomenon in canines. I got my information online from a 2017 paper by Robert A. Foster: Female Reproductive System and Mammae”, published in “ScienceDirect”: https://www.sciencedirect.com/topics/pharmacology-toxicology-and-pharmaceutical-science/pseudopregnancy which is about domestic dogs, but I think it’s safe to assume that coyotes might exhibit the same phenomenon. For how the process works you’ll have to click on the article above, but the relevant information is this:

It has been hypothesized that this condition is an adaptive response to allow non-breeding females to help raise offspring of the breeding female.54 Associated physical and behavioral changes are very broad in scope, ranging from none all the way to the equivalent of pregnancy. Included can be nervousness, guarding an area, making a nest (66.1% of nonpregnant females), abdominal distention, mammary gland development with or without lactation (78.6%)

Through the 16 years that I’ve been observing, I’ve seen many yearlings help raise the young of their parents, but only within the last several years have I seen this “double lactating”. So, my question is, would these be double-pregnancies (and therefore polygamous situations), or are the yearling daughters just “helping to raise their mother’s new pups” by contributing to the milk supply, among other things?

Coyote reveals her lactating state to me.

My observations are all visual, and I never go close to densites, and so I wouldn’t be able to tell which of these two potential situations exists in these four cases: in all cases, the lactating daughter also swelled up in size — but as you have read above, this is a symptom of pseudopregnancy. However, based on case #4 where the long-term alpha remained and was not replaced, and based on what we know about coyotes being monogamous, I’m now leaning towards the belief that these daughters are simply helping their mothers. By the way, in the cases before 2023, all of the lactating two-year-olds dispersed when the season was over, except one who remained until April of this year before leaving. In addition, all of the alpha mothers were about eight years old..

I’ve asked Dr. Benjamin Sacks at UC Davis if he can provide me with his knowledge of, or references to, these situations. AND, since we have the DNA from scats from some of these situations, we’ll be able to tell definitively what the situation is for that family — these are still being worked on. I’ll be following up with more once I find out more, but I wanted to go ahead and post this today, on Mother’s Day!

Leave a comment