In an earlier column about bears coming out of hibernation, I asked whether anyone had seen bears yet this spring on Lathrop land.
Well, sure enough, Carol Neubert sent me photos taken about April 6. She writes:
At about 9:00 in the morning Mama Bear and her two cubs appeared in our backyard. Mama went over to the tree line, lazily reclined on her back, and the two cubs proceeded to nurse. Two of our grandchildren (ages 6 and 3) were visiting and, needless-to-say, the bear visit was the highpoint of their stay.
If you think that this picture of the nursing mom looks like a huge blob of cubs pouncing on her–well, that’s how she might feel.
She’s been nursing them since January, in her den. Their birth weight was under one pound–the smallest birth weight in relation to the mother of any placental mammal. As they have grown big and strong, she may have lost up to a third of her body weight, which was 90-175 pounds. Now she is eating grass, herbs, Continue reading It’s Not Easy Being a Mama Bear→
No, we’re not talking about some old lesbians, though some of us, too, are “out” at Lathrop and feel warmly welcomed.
But today, we’re talking about our Lathrop creatures who have been hiding in dens or burrowing into the ground, coming out now as the weather warms, welcomed by Lathrop’s residents, who’ve been waiting for spring.
Of course, we have to begin with our bears. Has anyone seen a bear at Lathrop yet this spring?
If you don’t bring in your bird feeders, you may see them where you don’t want them–knocking down your bird feeder pole with one powerful swipe, or climbing onto your porch. Think about your garbage cans, too, and don’t leave open your garage door with bird seed or other goodies inside.
Several recent columns have featured pregnant Lathrop creatures. The most recent one was the porcupine, which is well defended against most predators, but has one special predator–the fisher–that knows how to overcome the porcupine’s defenses.
Also pregnant about now is another well-defended Lathrop resident–the skunk. Our skunk mom has emerged from her winter torpor–not quite a hibernation, but a slowing metabolism, during which her body temperature may have dropped 20 degrees. Invigorated by spring sunshine, she has mated with a polygamous dad, but for her, once is enough, and thereafter she has fought off all other suitors.
She’ll have her 4-8 babies in May or early June. She can dig her own den, but prefers to move into a used one, or, as some of us know, a spot under a porch. At 8 days old, the babies can emit their smelly defenses. Continue reading Expecting at Lathrop, Part 4→
After the last two weeks’ columns about coyotes and bobcats that eat poor little rabbits, perhaps it’s time to look at some pregnant vegetarians on our land.
Our porcupine–perhaps the one that Eleanor Johnson and her family saw in Addison’s Oak last summer–is a vegetarian. Mom has mated long ago–in late summer or early fall, when the male fought with other porcupines for her favors and performed an elaborate courtship dance (yes, dance), including spraying urine on her head. Eeeeeew.
Unlike our rabbits who gestate in a few weeks and our coyotes and bobcats who take a month or two, it takes seven months to make a porcupine baby. Our mom is giving birth about now to just one infant. (Ladies–in case you wondered, the quills are soft as the baby is being born; they harden shortly after birth.)
Our baby porcupine can forage for its own food within a few days after birth, though it will stay with its mother for about 6 months.
Well you thought this was going to be a column about an innocent little vegetarian, well protected against predators, no hunting, no blood, no guts. But in fact, mama porcupine does have to try to protect herself and her babies. Especially expert at attacking porcupines are fishers, which are members of the weasel family. They are elusive, but undoubtedly live here. Has anyone seen one on Lathrop land? Fishers attack porcupines with swift, darting bites to the head. When the porcupine is dead, they flip it over and start eating at the belly. Eeeeeew.
Last week’s column featured two of our pregnant Lathrop predators–the coyote and the bobcat. The column ended by asking, “What are all these hungry predators and their babies going to eat?
Well, one of their favorite foods is — Rabbit!
Talk about pregnant. Our rabbit moms–whom we ALL see in our lawns and gardens–will give birth 3 or 4 times this year, each time to 3-8 babies. The babies are sexually mature in only 2-3 months. This could be a math challenge for the students that Cranberry Lane resident Roger Herman tutors at the Williston School. Rabbit populations, notes one source, “are able to grow with staggering speed.”
Except, of course, that all our bobcat and coyote babies, and their moms and dads, will be eating rabbits. Without these predators, we could look like the Australian outback with every green shoot eaten, and, for population statistics, we would have to call in Huckleberry Lane resident Roger Howe’s math students at Yale. With average predators, however, only 15% of baby rabbits survive their first year. Aha! You students–multiply by decimals.
So Mama Rabbit, how do you protect your babies?
The mother rabbit usually feeds her babies under cover of darkness in early morning or evening, when a predator cannot easily “see” the mother returning to her nest. She feeds two to three times within 12-hour timeframes. The babies flip over onto their backs and nurse upside-down. The mother stands over them, ready to flee the nest at the first hint of a predator. Her milk is so rich that it takes only a minute or so for the babies’ stomachs to fill and for the feeding to be complete.
After 3-4 weeks the babies leave the nest. By then, they know by instinct how to camouflage themselves, what foods to eat, and what a predator is. They automatically know to run away from a predator in a “broken path” pattern, thus making it hard for a predator to catch them, or to freeze in the “you can’t see me” position.
It takes 6,000 to 9,000 caterpillars to raise one nest full of chickadees. Almost all caterpillars eat only native plants, not aliens.*
Plants don’t want to be eaten, so they evolve to make themselves poisonous, distasteful, or inaccessible to insect mouthparts. But, aha! each native insect has co-evolved to overcome the defenses of one or several native plants. Thus the monarch butterfly lays eggs only on milkweed–the only thing its caterpillars can eat. Facing a 90% decline in monarchs due in part of disappearance of milkweed, the National Wildlife Federation and others are mounting a national effort to increase milkweed plantings.
Butterflies, bees, and birds–that’s why we need native plants on Lathrop land, including our gardens. Natives can be as beautiful, orderly, and well-designed as aliens.**
There are one heck of a lot of pregnant females on our land at Lathrop right now. No, I’m not talking about us old folks becoming the new biblical Abraham and Sarah. I’m talking about the wild creatures that call our Lathrop land their home.
Our coyote couple–the ones we hear howling sometimes at night–has mated in February or March and is expecting a litter of 4-8 pups in April or May. The cute pup above was photographed by John Good of the National Park Service. The coyote family unit contains mom and dad, who mate for life, possibly 1 or 2 “teenage” coyotes called helpers (are they more willing than our human teenagers?), and perhaps other, non-mating adults who, if the alpha couple is killed, will mate like crazy and have bigger litters than usual. More at http://www.predatordefense.org/coyotes.htm
Our bobcat female has mated in late winter with a philandering dad whose territory overlaps hers and that of several other females. On the east campus, we see our bobcat passing through; resident Chuck Gillies photographed this one in his back yard. All winter, we see bobcat tracks in the snow.