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Home , Great horned owl, Rattlesnake, Roadrunner, Wrentit

Last Updated 2019 FEEDING RELATIONSHIPS TO MAKE FOOD CHAINS OR FOOD WEB This is a collection of information that may help to put together food chain examples in the and Food Chains Program. (See the notes by Barbara Wallach on how to prepare for the program.) The examples and the table of eating relationships are meant to be used as a reference. Just pick what you may find useful in your walk. Source: TP Docent Training Manual, Children’s Program visuals, Wikipedia.

Some terms The terms here are just in case that they may come up. Usually they are not part of the Children’s Program presentation. In simple terms a keystone species is one that is crucial in regulating or maintaining the populations of other species in an ecosystem. Most common examples are top predators, or what are called apex predators. Some examples: • Mountain lion. Or in its absence, . • Northern flicker (Colaptes auratus, woodpecker family) • Sharks in the ocean • Starfish in tide pools (the term keystone species was coined in a research on tide pools)

Umbrella species are those that if we protect them will help to protect many other species in the as well. They do not necessarily be keystone species. Torrey is one example. A foundation species is one that plays a strong role in shaping or structuring the biological community, that is the species provides the foundation of a habitat. The sagebrush is a foundation species of the coastal sage habitat. Decomposers include fungi, bacteria, / (FBI)

Food web – a collection of interconnected food chains (see illustration below) Most consumers are not specialized; they eat what they can find easily, meaning the more abundant preys depending on the season or climate. They are what we call generalists or opportunists. So a consumer can appear (participate) in more than one food chain, such that if we put a collection of food chains together, we find that the food chains are interconnected. These interconnected food chains form a food web. ______

1 Sample food chains The plant and tags of the Children’s Program can be a good way to make food chains with the students. The easiest is just to ask them what are producers or consumers. So let’s put these tags in categories first. (What follows are based on what are available. We’ll update the lists when new tags are made.)

Producers Any plant tag will do if we ask students what are producers. Something more specific to help make food chains: Seeds – Black sage, California Buckwheat, Torrey pine (the pine nuts in the seeds) Berries/fruits – Laurel , Manzanita, Prickly-Pear, Scrub oak (acorn), Toyon

Primary consumers Hummingbird Woodrat

Secondary consumers Antlion larvae Raven Wrentit

Predators, secondary or tertiary consumers Coyote Gopher Red-tailed

Omnivorous Coyote Raven Wrentit

2 Now, some examples to string the tags together to make food chains. The food chains listed below are not meant to be exhaustive, but just some ideas.

Seeds → Ant → Lizard → → Hawk Seeds → Ant → Lizard → → Coyote Seeds → Ant → Lizard → Raven Seeds → Ant → Antlion larva → Birds → Hawk Seeds → Birds → Hawk Seeds → Birds → Snakes → Coyote or Hawk Seeds → Woodrat → Bobcat or Coyote Berries → Birds → Hawk Berries → Raven → (the young or eggs) by Coyote or Great horn Berries → Coyote Berries → Woodrat → Bobcat or Coyote Berries → Woodrat → Snakes → Hawk → Rabbit → Bobcat or Coyote Cactus → Rabbit → Snakes → Hawk Cactus → Woodrat → Bobcat or Coyote Cactus → Woodrat → Snakes → Hawk (Insects, if a tag is available → ) Spider → Wrentit → Hawk ______

3 (secondary and tertiary consumers; many are omnivorous, so primary consumers too)

Caution: On many websites, what they say are small are better be rephrased as small mammals. On these websites, rodents refer to mice, , , etc. A telltale sign is that they list separately. But biologically speaking, rodents (order Rodentia) include squirrels, , , gopher, porcupines, beavers, guinea pigs, and hamsters. But and moles are not rodents. So the safest thing is just use “small mammals” in a walk.

Eats Eaten by Bobcat Small mammals including woodrats, squirrels, Coyote and mountain lion, the top predators. , and also gophers and moles. Also birds, , , and large snakes. Adult male , insects, and . prey on the young. Coyote Omnivorous and opportunistic; eats almost Mountain lion, ( in the past); killed by . anything, from small mammals to birds, snakes, At the apex if without the mountain lion and insects, to berries and grasses. Also carrion. Gray Omnivorous. Gophers, mice, woodrats, and Coyote and mountain lion. (Probably by birds of gophers. Manzanita and toyon berries. prey too.) Omnivorous; a wide range of plants and Coyote and mountain lion. (Probably by birds of such as fruits, insects, snakes, and rodents. prey too.) Most omnivorous animal, but prefers prey that is Coyote and mountain lion. (Probably by birds of easy to catch, specifically eggs, fish, prey too.) , and crustaceans. Also seeds and berries. Omnivorous and opportunistic: insects and larvae, Coyote and mountain lion. (Probably by birds of earthworms, grubs, small rodents, lizards, prey too.) , , snakes, birds, moles and eggs. Also berries, roots, leaves, grasses, fungi and nuts. Mice, rats, rabbits; occasionally birds, bird eggs, Coyote and mountain lion. (Probably by birds of , amphibians, fish. prey too.)

4 Birds (secondary and tertiary consumers; most are predatory; raptors are the and hawks) Smaller secondary consumers are in another table below.

Eats Eaten by Fish. But if need to, birds, snakes, small rodents. Raccoon and snakes raid their nests for eggs. Great Mainly on small mammals, esp. rodents. But Fox, coyote, raccoon, raven, and raptors can raid opportunistic, so also on larger mammals including their nests for eggs and hatchlings. . Eggs and hatchlings of predatory birds. Small birds (e.g. scrub ), reptiles and amphibians. Even fish and insects if need to. Pelican, Brown Fish. Also amphibians, crustaceans (and Gulls, bobcat and skunk on their eggs and occasionally birds) hatchlings. Birds, including pigeons, songbirds, gulls, [allaboutbirds.org] Gyrfalcons, , other waterfowl, shorebirds. If need to, they also hunt bats peregrines. And great horned owl on their eggs. and pirate rodents and fish from other raptors. Raven Omnivorous and highly opportunistic. Small Coyote (elsewhere wolf and mountain lion; also mammals, birds and eggs, amphibians, reptiles, and golden ). Great horned owl and other ravens even insects. Berries and fruit. Even as scavengers. can raid their nests for eggs. Red-tailed hawk Very opportunistic. Mainly small mammals like Raccoon, great horned owl can raid their nests for woodrats and other rodents, rabbits, shrews. Also eggs and hatchlings. small birds (including shorebirds), bats, lizards, snakes (including ). Even fish, crustaceans, insects, and carrion. Lizards, snakes (including rattlesnakes, gopher Coyote, raccoon, bobcat, skunk, and hawks. snakes), (including venomous ones). Also insects, , and small rodents. If need to fruit (esp. tuna from cactus), berries and seeds.

5 Snakes (secondary and tertiary consumers)

Eats Eaten by Gopher snake Gophers, ground squirrels and other rodents. Predatory birds, esp. red-tailed hawk. Roadrunner. Rabbits. Bird eggs. Lizards and snakes smaller than Coyote, (elsewhere, ). Snakes bigger than itself. itself. Pacific rattlesnake Birds, bird eggs, small mammals from rodents to Roadrunner, red-tailed hawk. California . rabbits. Small reptiles and amphibians. The Snakes bigger than itself (including gopher, striped juveniles eat insects. racer) Striped racer Lizards. But also rodents, birds, insects. Snakes [No confirmed source yet. Probably be eaten like smaller than itself. gopher snakes.]

Lizards (secondary consumers)

Eats Eaten by Horned lizard Harvester Snakes, hawks, roadrunner, coyote and fox. Western fence lizard Insects (, flies, caterpillars, ants, etc.), Roadrunner and other birds, snakes. Can also be by spiders, and scorpions; occasionally small lizards coyote and . including its own.

Birds (including insectivores, secondary consumers)

Eats Eaten by Bushtit Insects, including spittlebugs. Predatory birds (e.g. hawks), snakes. California Thrasher Insects (ants, , bees, beetles, caterpillars, Raptors. coyote, raccoon, bobcat. Eggs by scrub jay. moths, etc.). Also spiders and . Small fruit and berries, but also seeds, acorns. California towhee Mainly seeds. Also berries such as elderberry and Eggs eaten by snakes and raccoon (probably by poison oak. May also eat insects, including spiders others too). Predatory birds (e.g. hawks), mammals and millipedes. (e.g. coyote and bobcat)

6 Scrub jay Insects, fruits, nuts, berries and seeds and Raptors, ravens, owls, snakes. occasionally small animals. Known planters of acorns. Pine nuts. Also lizards, eggs and nestling birds. Wrentit Insects, spiders, caterpillars, fruit, and seeds with Known nest predators (eggs or nestlings) include more emphasis on seeds in winter. Seeds of poison scrub jay and snakes. Adults probably ditto other oak (Toxicodendron diversilobium) are especially small birds. important.

Spiders (Secondary consumers)

Eats Eaten by Argiope Small flying insects such as aphids, flies, Wasps and birds. , and Hymenoptera (wasps and bees). Trapdoor spider Arthropods (insects, arachnids); common prey Spider wasps. Small mammals. includes , , moth, and . Mainly insects like grasshoppers, beetles, and other (a spider ). Lizards, snakes, small spiders. Sometimes on small lizards. birds, coyote and foxes. (Elsewhere, large can eat frogs, toads, and small rodents.)

Insects (Secondary consumers and )

Eats Eaten by Antlion Ants by the larvae (also trap other small insects). Small reptiles, birds, beetles. Adults on nectar and pollen. Darkling beetle A general decomposer: dead insects, feces, decaying Hawks and other birds including raven, snakes, leaves, grass. But also other beetles and coyote. larvae. Lacewing Aphids by the larvae (a voracious general predator). Birds, bats, and larger insects.

7 Pollen and nectar. Yerba santa leaves. Ladybug Aphids, but also mites and other small insects. Moth Birds. Spiders. eggs. Some maybe on pollens.

Mammals (primary consumers)

Eats Eaten by Mule deer Wide variety of plants (very opportunistic): green Mountain lion, (gray wolf in the past), coyote. leaves, twigs, grasses. Rabbit Mainly grasses and seeds. Also clover, sunflower, Birds of prey (including hawks and elsewhere milkweed (more generally herbaceous flowering ), coyote, bobcat, weasel, rattlesnake. plants or forbs), prickly-pear cactus, and other And great horned owl on the young. young plant growth. Even bark if need to. (They get their from what they eat.) California ground Pine nut, prickly-pear fruit (tunas), wild cucumber Rattlesnake, raccoon, fox, weasel. seeds, flowers (ceanothus, bush sunflower, suncups) Gopher Plant matter, shoots, grasses, roots, tubers. Coyote, weasel, owl, bobcat, hawks. Pocket mice Seeds By all bigger predatory birds and mammals. Deer mice Seeds and plant matter; insect larvae and pupae. By all bigger predatory birds and mammals. Woodrat Seeds, fruits (berries), and prickly-pear cactus; also Hawks, owls, snakes, bobcat, coyote. fungi and inner bark. Also goosefoot, mountain mahogany, and even pine needles. (Bushy-tailed on only green vegetation, twigs, and shoots)

8 Insects (primary consumers; herbivores or parasites, decomposers)

Eats Eaten by Aphid Sucking on sap of many plants (but a given aphid Lacewings; ladybugs, spiders, wasps, mites, feeds only on one species of plant, monophagous). hoverfly larvae. Some species of ants "farm" aphids, A real pest in gardens and farms. protecting them on the plant they eat, and eating the honeydew that the aphids secrete. Cochineal Prickly pear cactus (as a parasite) Leucopis (fly); Hyperaspis (beetle) Harlequin bug Bladderpod in TPSNR. But it’s a pest on cabbage, Harlequin ladybird, parasitic flies and wasps. broccoli, radishes (aka cabbage bug). Harvester ant Seeds. Or just the fatty coating (elaiosome) of seeds. Lizards, esp. horned lizard. Antlion larvae. Leafminer fly Leaf tissue of many plants. Wasps Spittlebug Both nymphs and adults feed on the sap of many Spiders, mantids, wasps, and birds. plants. Termite A decomposer Spiders, beetles, flies, wasps and especially ants. Also frogs, reptiles, birds. (Elsewhere, mammals such as aardvarks and chimps.)

______

9 A simple food web illustration (this should print to 6” by 4”). This is by no means comprehensive or absolutely correct, but just enough associations to convey the concept. For example, the rabbit and lizard eat other things too but they are just not in this chart. Coyote eat berries but since there are none, yet, in this chart, an arbitrary association is made to the buckwheat.

Hawk Coyote

Bobcat Roadrunner Snake

Rabbit Squirrel Wood

Lizard

Harvester ant

Cactus pad Buckwheat seed Pine seed Acorn

We can also begin the explanation with a simpler chart:

10 Hawk Coyote

Bobcat Roadrunner Snake

Rabbit Squirrel Wood rat

Lizard

Harvester ant

Cactus pad Buckwheat seed Pine seed Acorn

______

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