Dispersal Maneuvers

Dispersing youngster.

Yesterday at dusk, I saw a dispersing youngster wandering through a neighborhood. He was not fast-to-flee, but rather carefully deliberate and much more aware of his surroundings than he let on. He kept out of the way and to the edges when the couple of people or cars were around, otherwise he used the street. He found a baggie and attempted “milking” it for what it was worth. It looked empty, but it must have retained odors from its previous contents because the coyote was interested in it. As I observed, I became aware of the coyote’s right hind foot: it was compromised, which you could see only from certain angles. Coyote legs in particular are thin and subject to injury — I’ve seen such injuries mainly from being chased by dogs. This guy soon headed to the bushes and I didn’t see him again. That’s about par for me for observing a dispersing coyote: I only ever see them fleetingly. This is because they are not in their own territories, but just passing through what might be another coyote’s claimed territory — in other words, trespassing.

If you look carefully, you can see his injured hind right leg in these photos. This did not appear to impede his movements, so the injury probably happened long ago.

Dispersal here in San Francisco seems to take place mostly during a youngster’s second year of life, although I’ve seen it as early as 9 months of age, and as late as 3 years of age. It takes place at any time of the year: there’s no actual “dispersal season”. The new pupping season has begun, with new pups having just been born — this is one of the times when some yearlings, due to big changes in the family, may decide to, or be prompted to, move on.

Coyote population is like a breathing bellows, expanding during the pupping season, and then shrinking back down after dispersal to the alpha pair, with possibly a couple of yearlings lingering a little longer before moving on. The yearlings who remain at home — and these can be either male or female — it’s not limited to just the females — serve as a great help in raising a new litter and in defending the territory, and they themselves eventually move on.

What are the features of dispersal — how is it achieved? I’ve seen parents drive youngsters out, I’ve also seen youngsters just pick up and leave when they are ready without cause, and I’ve seen siblings driving siblings out. Interestingly, opposing this process, I’ve seen parental feeding keep youngsters around well into their second year.

When a parent instigates the dispersal process, it appears to me to be driven by reproductive jealousy, as well as, sometimes by a crack in the hierarchical order. For this purpose, parents use silent intimidation (such as intense and prolonged intense staring) or physical intimidation (body slams, punches, bites) as well as hierarchy demands. Hierarchy is strong right from when the pups are born, with pups learning to lay low and hit the ground submissively at meetings with the parents. Sometimes I’ve even seen youngsters appear to shrink into themselves to look smaller when greeting parents, possibly in hopes of looking younger and thereby sticking around longer? It is mothers, or alpha females, who mostly intimidate their female youngsters — especially those who show an interest in Dad, and alpha males appear to intimidate and drive out the younger males, particularly if they show an interest in Mom. I saw the process begin with a youngster at 7 months of age in one family.

A form of sibling rivalry seems to include who is able to be next to a parent — it’s almost a kind of jealousy. I wonder if regular proximity might influence a parent’s decision to allow a certain youngster to stay on a little longer. Certainly that individual would have a survival advantage over a sibling who left — that’s one of the survival perks of having a territory to stay on. I just read in Wikipedia about starlings kicking their siblings out of the nest to insure they get all the parental attention and therefore a better chance at survival and reproductive survival — their rivalry goes as far as siblicide. Getting a sibling out of the way, out of the picture, seems involved sometimes with coyotes. Interestingly, Wikipedia even uses human step-siblings as examples of a siblings’ need to displace other siblings for their own advantage: did you know that murders in this group are higher than between other groups? This is how intense these rivalrous sibling feelings can be.

I’ve noticed that youngster males are allowed to remain in a family much longer when a Dad isn’t around — say, he died and another alpha male didn’t take his place — or when dad has become enfeebled by old age and may need the youngster to help defend the turf. I’ve seen such a male then move up into the alpha position — yep — becoming his mother’s mate.

It’s after leaving home that dispersal becomes dangerous for urban coyotes. This is due to cars — cars are their chief killers in cities, due to hostile territory-owning coyotes who drive them away, and due to unfamiliarity with new terrain. They appear to search for new homes mostly at night, when it’s safest for themselves.

BTW, a couple of times, I’ve seen a dispersing, “foreign” injured yearling youngster accepted as a visitor by an alpha female in another territory: it’s really altruistic behavior. I don’t know how common this is. More often, I’ve seen dispersing youngsters being repulsed by territorial owners.

Here are some dispersal directions and final destination I’ve been able to track in San Francisco (center photo — clicking on it will enlarge it for you):

To the left: rivalrous siblings duke it out. Center: some dispersals that occurred within the city (most youngsters move south and out of the city); Right: dispersal is a dangerous time for coyotes — cars are their chief killers.

During dispersal, a brave and strong yearling could end up fighting for a territory within the city where they detect weak or aging alphas — this happened in the Presidio in 2019. Or, a lucky coyote just might find a vacated niche here in the city — this happened at Bernal Hill in 2016. A youngster may wait it out on the periphery of a territory having assessessed one of the alphas to be weak, and then move in when the opening occurs: this happened in the Presidio only a couple of years ago. However, most dispersing youngsters seem to move south and out of the city because all territories within the city are already taken (per Presidio study).

In this video, a mother coyote wallops her yearling daughter to either disperse her or to instill fear in her so she won’t reproduce. Notice Mom is being aided by her son, her daughter’s younger brother, who appears to be simply copy-cating his mother’s mean behavior. In this particular instance, daughter was regularly cozying up to dad. This particular situation ended up with the parents leaving the territory to their daughter because she would not leave.

These next two dispersal maps come from the Presidio (©Presidio). The first map to the left details one coyote’s months of criss-crossings in search of a territory, even out of the city and back, and, the next map (in the center, below) shows her journey’s end in the Presidio: note there is no more wandering, she found her niche and sticks to it and keeps other coyotes out. Of 15 coyotes tagged and collared in the Presidio over a three year span, all apparently were killed by cars except one. In addition, the radio-collars and tags themselves created problems. Here (below right) is a deformed ear due to an infection caused by an ear tag, and her collar was supposed to fall off after one year for humane reasons, however, it malfunctioned and she has been burdened with it for 6 years and will be stuck with it probably now for the rest of her life. I’m not a fan of these gadgets, but the maps are fascinating.

The two maps to the left are from the ecologist at the Presidio©, based on recordings from a tagged and radio-collared coyote. To the right is what these gadgets look like: The ear-tag became infected and caused the ear to permanently flop; and the radio-collar itself was supposed to self-release after a year, for humane purposes, but it malfunctioned, so she’s been stuck with the collar for the past 6 years.

2 Comments (+add yours?)

  1. claire
    Apr 09, 2023 @ 13:59:48

    Why wasn’t the coyote burdened with the radio collar, darted and the collar removed?


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