Butterfly abundance this year: real or illusion

Michael Gochfeld gochfeld at eohsi.rutgers.edu
Sun Aug 17 04:43:28 EDT 1997

I've had several calls from local newspapers to comment on the abundance 
of butterflies which "everybody" notices this year. 

There truly is an APPARENT abundance in central and Northern New Jersey. 
Butterfly bushes are aflutter.  People notice these things. 
People at work comment on all the butterflies in their yard, even if 
they haven't planted a butterfly garden. 

The truth is that some butterflies are unusually numerous this year 
while others are unusually scarce. 

Eastern Tiger Swallowtails (Papilio glaucus) for example, are quite 
common, by any measure.   
Spicebush Swallowtails (P.troilus) are above average but hardly 
Cabbage Whites (Pieris rapae) were far above average in July (but many 
people think these are moths), and were conspicuous in gardens---but not 
along roadsides where most nectar sources were already dead from the 
Sulfurs (Colias) were extremely low, by contrast. 
Hairstreaks and Blues probably don't catch the eye of lay people, so 
wouldn't contribute to abundance or dearth, but Red-banded Hairstreaks 
(Calycopis cecrops) have been unusually numerous. 
	Moreover we're finding them in numbers on a European Mint 
(Mentha) which never gets anything else except a tiny emerald-colored 
bee and a striking wasp with a rufous-abdomen and a yellow-band proximal 
to the rufus. This seems to go to this mint preferentially. 
Great Spangled Fritillaries (Speyeria cybele) are up and would certainly 
catch people's attention, but as far as I can tell all other Nymphalids 
(including Satyrids) are way down---virtually no ladies or admirals 
(Vanessa) for example. 
Monarchs are low normal
Silver-spotted Skippers (Epargyreus clarus) are about normal, and this 
is the only skipper likely to attract attention.

So the conclusion is that butterflies appear numerous, but this is 

Nontheless most of the northern NJ butterfly counts had high species 
diveristy---record counts. 

In this extreme drought year, butterfly gardens really paid off. 
Virtually all of the field and meadow flowers were dead by early July. 

In previous year we've debated whether butterfly gardens are beneficial 
or are sinks, sucking butterflies out of real habitat. But this year, 
it's pretty clear that gardens are virtually the only place in our area 
to find butterflies.  Even gardens not designed for butterflies 
specifically, seem to have at least one Buddleia. I wish I'd bought 
stock in Buddliea a decade ago, because it's spread has been 

M. Gochfeld

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