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HolidayBuyer's Guide

Many monarchs in a cluster

Bring Back the Monarchs

Monarch trail

One on the ground

Flying

Monarch resting area

Catching the late sun

Lighthouse cluster

The emergence of the butterfly

A monumental migration

Butterfly crossing

Solo monarch

Monarch Grove Sanctuary

PG cluster

Big Lighthouse cluster

Bench

Monarchs on eucalyptus

Close-up

SANTA CRUZ, Calif.--For years, large populations of monarch butterflies have migrated to the central California coast each winter in search of stands of trees protected from the wind and cold. But since the early 1990s, the number of butterflies that make it to places like Natural Bridges State Beach here, or to the monarch sanctuary in nearby Pacific Grove, Calif., has dropped precipitously, from well over 100,000 per year to 10,000 or less today.

This is one of a very small number of clusters of monarchs that can be found today at Natural Bridges.

According to the experts, the reason for the dramatic fall in numbers is a general loss of milkweed throughout California, a plant that is required for the breeding of monarchs.

Now, as the population of monarchs that "overwinter" from late October through early March falls to dangerously low numbers, there is hope in the form of organized efforts to increase the amount of milkweed that is grown in California and elsewhere.

Caption by / Photo by Daniel Terdiman/CNET
In an effort to save the butterfly population, an organization called Monarch Watch is "initiating a nationwide landscape restoration program called 'Bring Back The Monarchs.' The goals of this program are to restore 19 milkweed species, used by monarch caterpillars as food, to their native ranges throughout the United States and to encourage the planting of nectar-producing native flowers that support adult monarchs and other pollinators."
Caption by / Photo by MonarchWatch.org
The entrance to the protected monarch grove at Natural Bridges State Beach in Santa Cruz, Calif.
Caption by / Photo by Daniel Terdiman/CNET
Although most of the thousands of monarchs at Natural Bridges are hanging from trees, or are flying around at 35 feet or higher, this one butterfly was crawling on the ground, adding a splash of bright orange to the otherwise gray and brown landscape.
Caption by / Photo by Daniel Terdiman/CNET
A group of monarchs flies around in the trees at Natural Bridges State Beach in Santa Cruz, Calif.
Caption by / Photo by Daniel Terdiman/CNET
The sign at the front of the monarch resting area in Natural Bridges.
Caption by / Photo by Daniel Terdiman/CNET
A cluster of monarchs catches the last rays of the afternoon sun at the Monarch Grove Sanctuary in Pacific Grove, Calif.
Caption by / Photo by Daniel Terdiman/CNET
Another cluster of monarchs rests in the trees at Lighthouse Field State Beach in Santa Cruz, Calif.
Caption by / Photo by Daniel Terdiman/CNET
According to a sign at Lighthouse Field State Beach in Santa Cruz, Calif., "Using an unusual survival strategy, monarchs lay eggs on toxic milkweed leaves where young caterpillars will hungrily forage. The caterpillars will accumulate these poisons and carry them into their adult stage, making them an untasty diet for most predators."

The illustration shows the emergence of a butterfly from its chrysalis form, and prior to that, its caterpillar form.

Caption by / Photo by Daniel Terdiman/CNET
According to this sign at Lighthouse Field State Beach in Santa Cruz, Calif., "No other butterfly travels as far as the monarch--every fall they migrate as much as 1,500 miles to reach the moderate climate of their ancestral winter refuges. These tiny adventurers, four to five generations descended from the monarchs that wintered here last year, cluster on 'butterfly trees,' colorful wings closed. In balmy weather they flutter about, feed on flower nectar, and mate.

"Egg-laden females journey north in spring, stopping to deposit eggs on milkweed plants. In a few days, the caterpillar eats its way out of the egg casing and feeds on the milkweed. It sheds its striped outer skin multiple times as it grows, and eventually the skin hardens into a hanging shell-like chrysalis from which the adult butterfly emerges."

Caption by / Photo by Daniel Terdiman/CNET
A sign at Natural Bridges State Beach announces the monarchs.
Caption by / Photo by Daniel Terdiman/CNET
A monarch hangs off a tree branch.
Caption by / Photo by Daniel Terdiman/CNET
The entrance to the Monarch Grove Sanctuary, in Pacific Grove, Calif.
Caption by / Photo by Daniel Terdiman/CNET
Although its Web site suggests that 25,000 monarchs overwinter there each year, there are less than 5,000 this winter at the Monarch Grove Sanctuary in Pacific Grove., Calif. This is one of the small number of clusters of butterflies that can be found there.
Caption by / Photo by Daniel Terdiman/CNET
A large cluster of butterflies at Lighthouse Field State Beach in Santa Cruz, Calif.
Caption by / Photo by Daniel Terdiman/CNET
A bench in the shape of a monarch butterfly at the Monarch Grove Sanctuary in Pacific Grove, Calif.
Caption by / Photo by Daniel Terdiman/CNET
A cluster of monarchs rests in the eucalyptus leaves at Natural Bridges State Beach in Santa Cruz, Calif.
Caption by / Photo by Daniel Terdiman/CNET
A close-up of a cluster of monarchs.
Caption by / Photo by Daniel Terdiman/CNET
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