A tough year for monarch butterflies has ended, and about all you can say in its favor is that it wasn't the worst year for them.

Only a fraction of their usual number made it to South Jersey. They arrived too late to produce more than one generation for the trip back to the mountains of Mexico.

Several readers have written to say they saw the same in their gardens and yards - either a complete absence of monarchs or just a couple.

Allen Lacy, the great garden writer, said he knows of just one monarch butterfly being spotted in the Linwood Arboretum gardens this year.

Nature photographer Tamra Walker, of Staten Island, New York City, was there that day taking pictures for her website, tamra walker.com, and sent him a photo of the lone monarch.

In his own Linwood garden, the butterflies are attracted to a variety of New England aster named Hella Lacy, after his wife.

"In past years, usually we had a cloud of monarchs swarming around it for 10 days or so," Lacy said. "This year, not a one!"

Another author, Pat Sutton, of Middle Township, reported a similar but slightly better experience in her blog at www.patan claysutton.com.

She said in mid-September she had seen 11 monarchs in her garden and she had found just one monarch caterpillar, far fewer than normal.

Sutton leads tours of habitat gardens throughout Cape May County. She said those gardeners reported a similar paucity of monarchs this year.

Our first monarch arrived July 26 at our milkweed-rich garden in Linwood, and several others straggled in during the next two weeks. They produced perhaps a dozen caterpillars. In the second half of September, we saw several fresh butterflies and watched a couple emerge.

At the end of October, the Monarch Monitoring Project completed its 22nd year of systematically counting the butterflies as they pass through the Cape May Point area on their long trip to Mexico.

The count produces an average number of monarchs seen per hour by sending observers slowly over the same 5-mile route three times a day from Sept. 1 to Oct. 31.

Last year, the observers saw an average of 183 monarch butterflies an hour, a good year but well shy of the 360 an hour seen in 1999.

This year, the Monarch Monitoring Project counted just 13 an hour, and weekly counts never got above 28 an hour - no spectacular movement of monarchs this year.

At least it wasn't the worst year for monarchs; that was 2004, when nine an hour were seen.

This year, as in 2004, the winter population in the monarchs' Mexican sanctuary was unusually small. This spring was wet and cold in the southern states that first host monarchs moving north, delaying and reducing the next generation that continues the migration.

Those conditions are variable, but herbicide use and clearing of suburban weeds has permanently vanquished much of the milkweed that is the only food plant for monarch butterflies.

Federal ethanol mandates have resulted in much of the vast Conservation Reserve Program lands being converted to corn crops for ethanol and herbicide use.

The falloff in monarchs in 2004 prompted some to worry that America's most famous migratory butterfly could go extinct, but Jeffrey Glassberg, president of the North American Butterfly Association, says that's not the danger.

The concern, said the author of the handy "Butterflies Through Binoculars" guide, is that the migration won't be sustainable, and monarchs will become a local, southern species.

That would be quite a loss for gardeners and nature lovers in most of the country.

Contact Kevin Post:

609-272-7250; KPost@pressofac.com