Hairy Woodpecker (male) - Dryobates villosus
If you've seen a bird flying around with an insect in its beak lately, chances are it's on the way to a nest to feed its offspring. In the spring and summer, 96% of terrestrial birds feed their nestlings invertebrates, not berries or seeds. Nestlings are the babies still in the nest, that have not yet fledged. The list of edible invertebrates is quite lengthy and includes caterpillars, beetles, beetle larvae, ants, butterflies, moths, termites, wasps, bees, grasshoppers, crickets, earthworms and spiders.
Hairy Woodpeckers feed on wood boring beetles and their larvae, ants, bees, wasps, butterfly caterpillars, grasshoppers, crickets, cockroaches, spiders and millipedes. They regurgitate digested foods to feed their young nestlings. As nestlings mature, they are fed whole invertebrates. There are usually 4-7 nestlings in a nest. The nestlings are fed approximately 7 times an hour, from sunrise to sunset, for 28-30 days! That's a total of 3,000 feedings before the nestlings leave their nest!
Red-breasted Sapsucker (male) - Sphyrapicus ruber
Red-breasted Sapsuckers are another common woodpecker in our neighborhood. The one pictured above has a mouthful of ants! Sapsuckers feed their nestlings ants, caterpillars, spiders, and mayflies every 2 minutes from dawn to dusk! There can be 4-7 nestlings in a nest!. The nestlings fledge in 23-28 days. So that's at least 10,500 invertebrates that get delivered to the nestlings by the parent birds!!! Wow!!!
Scudderia Katydid nymph - Modoc Carpenter Ants - Mason Wasps
Microcentrum rhombifolium - Camponotus modoc - Euodynerus foraminatus
Horned Lark (male) - Eremophila alpestris
Lately I've seen several birds with lots of caterpillars in their beaks! Horned Larks feed their nestlings caterpillars, beetle larvae, grasshoppers, sowbugs and earthworms! On average a Horned Lark feeds its young every 5-6 minutes! That's 20+ trips in an hour, times 14 hours in a day (more or less) equals a total of 280 trips in one day! There are 2-5 nestlings in a nest. The nestlings usually fledge (leave the nest) in 10 days. So 10 days times 280 equals 2,800 insects/invertebrates to feed one group of nestlings!
Brewer's Sparrow (male) - Spizella breweri
Caterpillars can be the main food for many nestlings. 90% of the local caterpillars need native plants to survive. In fact most caterpillars are "host specific", in that they feed on one species of native plant in their larval stage. Look up the butterflies and moths in John Muir Laws' book The Laws Field Guide to the Sierra Nevada, to find the host plants for their larvae (caterpillars).
Caterpillars - unknown species
As Kate Marianchild states in her book Secrets of the Oak Woodlands, "Caterpillars are Mother Nature’s equivalent of mother’s milk and Gerber’s baby food, the ideal and irreplaceable food needed for most baby songbirds to survive. They’re soft and squishy and full of fat and protein and carbohydrates."
Olive-sided Flycatcher with wasp - Contopus cooperi
The Olive-sided Flycatcher feeds its nestlings mainly flying insects, such as dragonflies, flies, bees, wasps, flying ants, moths, and grasshoppers. On average, there are three nestlings in a nest. Cornell didn't have any information on how frequently the adults feed the nestlings! The nestlings fledge in 15–19 days. I'm sure the parents make thousands of trips feeding their young.
Steller's Jay with insect - Cyanocitta stelleri
Steller's Jays probably feed their nestlings wasps and wild bees, beetles, caterpillars and moths, spiders, and grasshoppers. Surprisingly Cornell didn't have any data on the type of food or the frequency of feedings! They usually have 4-5 nestlings, which fledge in 16 days. I would imagine they make thousands of trips feeding their nestlings until they fledge.
Small Milkweed Bug - Yellow-faced Bumblebee - Small Minnow Mayfly
Lygaeus kalmii - Bombus vosnesenskii - Callibaetis spp.
Papilio rutulus rutulus - Papilio eurymedon
Garden Butterflies!
There has been an influx of butterflies in our garden lately! Luckily these weren't eaten while they were caterpillars, but they can still be eaten as adults. In the meantime they are pollinating flowers, drinking nectar, mating, and laying eggs! A butterfly usually lays between 100 to 300 eggs, which hatch into caterpillars within 3 to 8 days. The following information from sciencing.com explains this process.
"Egg Formation: Butterflies are oviparous, meaning they lay eggs. They breed as many animals do—eggs from the female insect are fertilized by sperm from the male. The female butterfly stores the male’s sperm in a bursa, or sac, until she is ready to lay eggs. Depending on the species, females lay eggs one at a time, in clusters, or in batches of hundreds. Butterflies lay an average of between 100 to 300 eggs, although some species may only lay a few dozen, others can lay as many as a thousand or more.
Silver-Spotted Skipper - Pipevine Swallowtail
Epargyreus clarus - Battus philenor hirsuta
Physical Characteristics: Butterfly eggs vary in size—from about 1 to 3 mm in diameter. The eggs can be smooth or textured, their shapes can be oval or round, and their colors can be yellow, white, green or other shades, depending on the species. The zebra longwing butterfly (Heliconious charitonia), for instance, produces eggs that look like tiny cobs of corn while the eastern black swallowtail butterfly (Papilio polyxenes asterius) produces smooth, pale-green, globe-shaped eggs.
Clodius parnassian - Parnassius clodius sol
Early Egg Stage: Butterfly eggs are normally attached to a plant--usually the leaf--with a special fluid. This glue holds the eggs to the leaf in such a way that they cannot be separated without destroying the eggs. Small funnel-shaped openings called "micropiles" can be found on top of each egg. This is where water and air enter while the egg is developing. Each egg is surrounded by a chorion, a hard outer shell that protects the larva. Some shells have raised ribs.
California Sister - Lorquin's Admiral
Adelpha californica - Limenitis lorquini
Egg Development: Inside each egg, a yolk can be found that serves as nourishment for the developing larva. A butterfly egg hatches after three to eight days depending on temperature and season of the year. A change in the egg’s color before hatching is normally visible. After hatching, some caterpillars eat their own eggshells as their first meal but most of them eat parts of the plant that the eggs were laid on.
Survival: A female butterfly lays a great number of eggs. They also take special care of where they lay their eggs. The eggs need to be kept warm and must have the appropriate moisture or they will either rot or dry out. Normally, the eggs are attached to the underside of a leaf so they are kept safe from predators. A big portion of these eggs will not hatch to become butterflies as they are vulnerable to many predators such as birds, spiders, other insects and small mammals. Of the few hundred butterfly eggs laid, very few will reach adulthood."
Veronica Lake - 6/21/23
My friend Nancy and I decided to hike the Round Lake Trail last Thursday, but only got as far as Veronica Lake due to the snow. There was still about a foot and a half of packed snow on 70% of the ground. The trail was obscured in many areas, and there were several fallen trees on the trail. It was lovely, but the going was slow. Looks like it will definitely be another week or two before the trails are truly open!
Whose scat is that?
Where are the deer and the bears?
What's happening on the river?
Check back next week for the answers to these questions and more!
Your questions and comments are greatly appreciated. Please feel free to email me at northyubanaturalist@gmail.com. Thanks!.
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