Tag Archives: breeding

Black-tailed Jackrabbit – Page 17 .. The 100 Day Project (2026)

August 24, 2026

Black-tailed Jackrabbit (Lepus californicus)

—aka—

American Desert Hare, Jackass Rabbit

One of the largest hares in North American, the Black-tailed jackrabbit can grow up to 2 feet long and weigh from 3 to 6 pounds. In our neighborhood this is certainly true! We always love when these big hares move around our home, even if Luna is always keen to chase them away! This past spring a litter of four young Black-tailed jackrabbits (called leverets) spent a few weeks of their lives playing tag with each other around our gravel driveway and under the adjacent pinyon, juniper, oak, and mahogany. They seemed oblivious to our gawking and to Luna’s whining. Their comically clumsy antics were so funny to watch; we could count on a great show every day — either early in the morning or just before sunset. Then one day they were gone! For a week afterwards, we’d occasionally see them moving together through the subdivision ….. bounding after each other as they playing hide-n-seek. The last time we spotted them as a group was heading up towards our big community hilltop water tank. I like to think those now grown-up hares still come by the house once in a while to grab a bite to eat and say “Hi.” Who knows, they’re probably making babies of their own! 

Here’s some things about Black-tailed jackrabbits you may not have known. All of the following was definitely new to me.

Population densities: The Black-tailed jackrabbit is a very common hare living in the western U.S. and Mexico. Their population densities typically range from fewer than 25 (when habitat conditions are poor) to nearly 500 animals per square mile (/mi2) (during peak years).  You can count on numbers fluctuating every 6-10 years due to food supply, weather and disease. The New Mexico State University Extension Service reported when rangelands heavily infested with hundreds of hares/mi2, compete significantly with livestock for forage.

Habitat consisting of a mosaic of mixed-forbs, grasslands and shrubs are occupied by Black-tailed jackrabbits at elevations from sea level up to 10,000 ft. Because they don’t migrate (or hibernate) during winter, these hares use the same habitat within a 0.4–1.2 mi2 area year-round. Preferred habitat provides not only food, but shelter and cover.

One of the four of our young spring black-tailed jackrabbits – a leveret

Common habitat types include sagebrush, creosote bush and other desert shrub lands; Palouse, shortgrass and mixed-grass prairies; desert grasslands, open-canopy chaparral; oak and pinyon/juniper woodlands; early serial stage low- to mid-elevation coniferous forests. They are also common in and near crop lands — especially alfalfa. 

Diet is composed of various shrubs, small trees, grasses, and forbs.  Shrubs generally make up the bulk of fall and winter diets; grasses and forbs are eaten in spring and early summer. This pattern and plant species varies with climate.

Breeding, depending on location, typically peaks in spring, but may continue year-round in warm climates. The breeding season is variable depending upon latitude and environmental factors. In the northern part of their range (Idaho), Black-tailed jackrabbits breed from February through May. In Utah, they breed from January through July (over 75% of females are pregnant by April). The Kansas breeding season extends from January to August. Two peak breeding seasons corresponding to rainfall patterns and growth of young vegetation occur in California, Arizona and New Mexico. In Arizona, breeding peaks during winter (January–March) rains and again during June monsoons.

Two more of the four spring leverets – something has their attention off to their left

Birth: The female (doe) about to give birth doesn’t prepare an elaborate nest. She drops her young (leverets) in shallow excavations called forms that are no more than a few centimeters deep. The doe may line her form with fur prior to giving birth, but some just use existing depressions on the ground with no further preparation.  

Young (leverets) are born fully furred with eyes open; are well camouflaged and mobile within minutes of birth. As all mothers (does) are inattentive (she gives birth and leaves them alone) the ability of leverets to hit-the-ground-running within minutes of delivery works perfectly for her once-a-day nursing schedule! The average litter size is around four, but may be as low as two and as high as eight in warm regions. 

Leverets leave their birth form to find their own individual hiding spots just 2-3 days after they are born. They typically sit very still during the day, until it’s time to rejoin their mother and litter mates when she’s ready to nurse (either at dawn or dusk). Nursing occurs over a period of about 4-5 weeks until the leverets are fully weened.

Prey species: Black-tailed jackrabbits are an important prey species for raptors and carnivorous mammals, such as eagles, hawks, owls, coyotes, foxes, and wild cats. Rattlesnakes and bull snakes prey on the young hares, as do raccoons and striped skunks.

Parasites hosted by the hares include fleas, ticks, lice and mites; trematodes, crestodes, nematodes and botfly larvae are also found internally. Diseases affecting Black-tailed jackrabbits in the West are tularemia, equine encephalitis, brucellosis, Q fever and Rocky Mountain spotted fever. Jackrabbits infected with tularemia die very quickly.

A Cautionary Note: The high prevalence of parasites and disease in wild jackrabbits affects human predation. As a result, many hunters will not collect the hares they shoot. Those who do are well-advised to wear gloves if handling carcasses and, if intended as food, should cook the meat thoroughly to avoid contracting tularemia. Most jackrabbit hunting is done for pest control or sport.

Playing a game of “tag” in our driveway

Etymology

Scientific name: Lepus californicus, translates directly from the classic Latin word Lepus for “hare” — and californicus, a new Latin suffix and geographic identifier meaning “of or from California”, which indicates the region where the type specimen was first documented.

The Common name: “Black-tailed jackrabbit” is really a misnomer. Even though these plant-eating mammals look similar to true rabbits, taxonomically are actually hares. (This got me wondering what exactly are the differences between rabbits and hares —so I made the following table comparing the two.) …… And now, back to the common name “Black-tailed jackrabbit.”  

“Black-tailed” —— named, of course, for their black tail.

“Jackrabbit”   —— this name is a more modern version of the mid-19th-century term “jackass rabbit,” given by early settlers who compared the animal’s very long ears to those of a donkey. You’ve got to admit, there is a lot of similarity in ear size!

And that’s all for now, folks! 

…………………………………………………………………………………………………

Do you live in a neighborhood with Black-tailed jackrabbits? If so, let me know!

‘Hopping’ you found this interesting!

As always, thanks for bounding by!

References: britannica.com; extension.nmsu.edu; iNaturalist.org; nationalgeographic.com; wikipedia.org

The Life and Times of the Lanceolated Chafer

The Case of a Mysterious Wormy Thing

July 9, 2026

This is the third year in a row that I’ve noticed these seemingly unremarkable-looking brown beetles “hiking” along the rock pile 2-track road. They appear all at once, about mid-June, then vanish after several weeks. This year (2026) these scruffy/fuzzy beetles, know as Lanceolated Chafers (Phyllophaga lanceolata), really caught my attention, especially after finding myself at ground zero of a mass male Flash Mob1 !!! From all directions, determined (and awkwardly) flying male chafers were dodging my legs to land on top of a lone female beetle frantically struggling against an earlier arriving male. His prickly lance-like legs had pinned her to the ground so she was lying on her side unable to use her legs. While she squirmed at my feet, newly landed beetles tried to fling off the original male to claim their rights to the female. Males continued to land until there must’ve been 30 or more, with fights breaking out everywhere, on top of the female and all around my feet. Each male was jousting to be victor. 

Males arriving, fights break out

But a victor of what? Was this some sort of mating ritual? Had the female released highly potent pheromones to attract a mate? If so, how far did her “call” drift on the wind to bring together so many males at one time? Did she intend to call only one male, or was her purpose to entice a stampede? If she anticipated a herd, was her intent to mate with the first one (the fastest?) to arrive? Maybe she hoped for battles and skirmishes to ensue, where the strongest of all males would win her favor(s)? This still remains a mystery, as I couldn’t find anything in the literature to explain this behavior? 

While pondering these questions (and daring not to move my feet for fear of squishing one of the many male pile-ups), I bent over for a better look. It was then I noticed an opaque white, worm-like thing slowly emerging from the female’s abdomen! “What could this be?” ….. 

Was it a larva? Probably not ….. Female chafers don’t give live birth; they lay eggs in the soil beneath their favorite host plants (such as mallows), where they hatch into grubs that remain underground for up to two years before emerging as adult beetles. 

Five males fighting for the female (notice how much larger she is than a male). Bit of a skirmish, left side.

Was it part of or the actual female genitalia? Maybe? I’m still searching for information about that notion.

Was it part of the male genitalia that had somehow broken off inside the female during insemination? Is that even possible? Again, still searching for answers about chafer sex.

Three males with the female (notice the “wormy” thing). One male, lower left, apparently confused?

For another 5 minutes I closely observed the squirming female laying helpless on the ground fighting off numerous suitors while still displaying the wormy “thing.” As more males continued to arrive, crash-landing on other grounded males and adding to the chaos, something changed. Can’t explain what happened, but in a matter of 15 seconds all the males stopped their aggressive fighting and took flight; the female uprighted herself (regaining her dignity?), quickly walking away like the nothing unusual had just happened. I watched her go, noticing she was no longer in possession of the wormy “thing,” and couldn’t find it anywhere at or near the scene! 

The party is over. A male walking away, looking for a mallow to snack on.

After-math

Over the next several days, nary a chafer was found! Had all the males satisfied their natural desires? Had all the females become pregnant, laid their eggs and vanished? “After” doing the “math” on the days following the event, I counted only two beetles walking the 2-track road, one headed north — one headed south. Scouts? ….. Because Lanceolated Chafer adults only live 1-2 months, and because none have been seen since the last two, that may be the end of sightings for this year. While there’s still the occasional pack of ants dragging away a dead beetle to share with their colony, the legacy of adult chafers lives on. Recently-laid eggs will hatch after only 18 days into white or cream colored, C-shaped larvae. Those grubs will munch away on mallow and grass roots for the next 1-3 years until a perfectly warm mid-June day, sometime in the future, the adults emerge from the soil to complete their life cycle. 

Epilogue 

Since most chafer beetles are nocturnal (active at night), if you’ve seen an adult during the day, it may have been the Lanceolated species which are diurnal (active during the day).  And you may have unwittingly encountered any of the chafer species found in North America……. 

An exhausted male, a bit off balance, as he feeds on mallow leaves.

…….. If you’ve ever seen one or more of your carefully-tended, vigorously-growing garden plants up and die overnight, it may have been victimized by root-living chafer grubs.

…….. If you live in the central or eastern U.S., grubs may be feasting on the roots of agricultural crops, like corn, soy, or sunflowers. Headline news is sure to cover the story of devastation and financial ruin brought on by the voracious chafer beetle larvae, complete with video of farmers holding a handful of grubs dug from below the soil surface.

Have you experienced one of these close encounters?

Hope you’ve found the “Life and Times of the Lanceolated Chafer” interesting (or maybe educational, peculiar, or maybe even fascinating!?!). Let me know what you thought.

As always, thanks for stopping by!

1 A flash mob is defined as a large group of people who suddenly assemble in a public place, perform a brief, pre-arranged action (like a synchronized dance), and then quickly disperse. Flash mobs are typically organized online via social media or viral messaging for entertainment or artistic expression. I think this definition nearly perfectly fits the chafer beetle dance I was witness to on that fine mid-June morning somewhere along the 2-track rock pile trail.