SEEING INSECTS AT QUAIL RIDGE
A number of interesting insects can be observed
at Quail Ridge, mostly in the spring. Some of the more conspicuous
include:
Butterflies:
Among the most colorful and easily seen insects at Quail Ridge are
the pipevine swallowtail butterfly (Battus philenor), whose
larvae feed on pipevine (Aristolochia californica), the
chalcedon checkerspot butterfly (Euphydryas chalcedona),
whose caterpillars are common on bush monkeyflower (Mimulus
aurantiacus), and the California sister butterfly (Adelpha
bredowii), whose larvae feed on oaks (Quercus spp.).
Early in spring you can see the brightly colored, spiky (but not
hairy) caterpillars on their host plants. Later in spring the even-more-brilliant
adults can be observed nectaring at buckeye trees (Aesculus
californica) and other plants. The mass emergence of adult
pipevine swallowtails in April is a truly spectacular sight.
Butterflies are the one group of insects you can
easily identify to species using a field guide, such as A Field
Guide to Western Butterflies48
or Butterflies of North America43.
Additionally, the Quail
Ridge butterfly list is essentially complete. Bill Patterson
and Greg Kareofelas‘s observations of the 66 butterfly species
at the Reserve, including what plants the caterpillars feed on and
what time of year the adults are active, comprise this infomative
list.
Moths:
The list of moths collected
by Greg Kareofelas and Bill Patterson at Quail Ridge continues to
grow every year. Most of the species are inconspicuous both as caterpillars
and adults, but caterpillars of several species are sometimes seen
in large numbers devouring the foliage of oaks in spring. During
outbreak years for the Pacific tent caterpillar (Malacosoma
constrictum, Lasiocampidae), you may see hundreds of reddish-brown,
hairy caterpillars eating oak leaves or crawling on the ground beneath
trees. The fruit-tree leaf-roller (Archips argyrospilus columbiana,
Tortricidae) also sometimes has huge outbreaks on the blue oaks
at Quail Ridge. Other oak defoliators that are common in the region,
but have not been seen often at Quail Ridge, are the California
oakmoth (Phryganidia californica, Dioptidae), which has
hairless large-headed caterpillars, and the western tussock moth
(Orgyia vetusta, Lymantriidae), whose caterpillars have
a row of white “hairbrushes” down their backs.
Bees:
There are at least 40 species of bees at Quail Ridge (see
bee list). Most are natives except for the familiar European
honey bee, Apis mellifera, a generalist flower visitor,
and a medium-sized leafcutting bee, Megachile apicalis,
from the Mediterranean area, a specialist on the invasive weed yellow
starthistle (Centaurea solstitialis). Most of our native
bees are solitary ground-nesting species, except for the large,
fuzzy, colorful bumblebees, Bombus spp., which live in
colonies.
In early spring, large bees may be heard buzzing
loudly around manzanita (Arctostaphylos manzanita) shrubs
in flower. The large fuzzy gray Habropoda depressa, and queens of
the yellow-and-black striped Bombus melanopygus, are among those
you may see quickly sipping nectar from the bell-shaped white flowers.
On buttercup (Ranunculus californicus) flowers, you can
see males and females of the solitary ground-nesting Andrena caerulea,
which specializes on buttercup pollen to feed its young. They are
slender and dark metallic bluish-green, and about half as long as
the diameter of the flower. Males are smaller and more slender than
females and have white hairs on their faces. Females gather pollen
into special brushes on their hind legs that appear to get larger
and more yellow as they accumulate pollen. On redbud (Cercis
occidentalis), you can observe honeybees, bumblebees, and a
variety of native solitary bees. The solitary bees include the blue
orchard bee, Osmia lignaria propinqua, a honeybee-sized
metallic blue species that is available commercially for pollination
of orchard and other crops. Smaller bees belonging to the sweat
bee family (e.g. Halictus, Evylaeus, Dialictus) glean pollen
from redbud flowers that have been opened by larger bees.
Ants: There are probably about
40 species of ants at Quail Ridge. Easily seen species include:
the seed harvester Messor andrei, a large black ant whose
nest entrances are typically decorated with large piles of seed
chaff; the velvety tree ant Liometopum occidentale, an
orange and gray species that forms large foraging lines on the trunks
of oak trees; and the carpenter ant Camponotus semitestaceus,
a very large red and black species that makes conspicuous crater-shaped
nest entrances on the ground.
Other notable species are the army ant, Neivamyrmex
nigrescens, a nocturnal marauder that attacks other ant colonies,
and Pseudomyrmex apache, a bright-orange species that lives
and forages on manzanita shrubs. Both of these species are among
the northernmost representatives of tropical groups. Manzanita (Arctostaphylos
manzanita) is a key plant species for Pseudomyrmex
and other arboreal ants because older plants have abundant cavity-riddled
dead wood that provides nest sites for ants, adjacent to live wood
that provides moisture.
Gall wasps: Galls are modifications
of plant growth induced by other organisms. The oak species at Quail
Ridge provide many fine examples of twig and leaf galls caused by
wasps of the family Cynipidae. The galls of each wasp species are
distinctively different. The most familiar one is the oak apple
gall, a large smooth gall found on valley oaks (Quercus lobata),
caused by the tiny cynipid wasp Andricus quercuscalifornicus.
The cynipid wasp Antron douglasii induces two types of
galls on valley oaks and blue oaks (Q. douglasii): pink
spiny turbans in summer, and white berry-like ones in early spring.
Other galls range from simple woody swellings to exotic shapes like
artichokes or sea urchins. Moreover, each kind of gall supports
a small community of parasites and other dwellers, usually other
kinds of wasps, that are specialized to live in the gall of a particular
cynipid species. See the Fremontia articles by Russo51
and Schick52 for
more about the fascinating ecology of Californian oak galls. A good
comprehensive reference is Russo’s Plant Galls of the California
Region50.
Aquatic insects: The man-made
stockponds on Quail Ridge contain complex communities of native
aquatic insects. These
include many beetles (e.g. Dytiscidae, Hydrophillidae), dragonflies
and damselflies (e.g. Coenagrionidae, Libellulidae, Aeshnidae),
Mayflies, true bugs (e.g. Bellostomatidae, Corixidae, Gerridae,
Notonectidae), and others. One of the most impressive of the pond
residents is the 7 cm long giant water bug, Lethocerus americanus.
Herpetologist Mike Benard has seen this voracious bug eat the tadpoles
and adults of the Pacific treefrog, Hyla regilla, a rare
example of an invertebrate preying on (as opposed to parasitizing)
a vertebrate (see the header)! Look in the stock ponds to see what
other aquatic insects you can find.
There are also several streams on the Reserve.
These are largely ephemeral, but contain many interesting groups
of insects. In the winter through early summer, large numbers of
water striders (Gerridae) fill the many pools of the stream. Also
in the stream are aeshnid dragonfly nymphs, which possibly prey
on the newt larvae that share the pools with them. Other notable
residents of the streams are dobsonflies (Corydalidae), large Dipteran
larvae, and club-tailed dragonflies (Gomphidae).
Photo Credits: Title, Giant Water
Bug (Mike Benard),Vanessa annabella and Western Tussock
Moth (T. W. Davies), Bumbus californicus (Tom Greer), Ten-spot
skimmer dragonfly (Gerald and Buff Corsi). For more pictures see:
http://elib.cs.berkeley.edu/photos/browse_imgs/insect.html
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