Thank you Dennis for suggesting that we not dismiss decline of nocturnal
(and crepuscular) flying insects as a possible significant factor in
nighthawk decline. I spend a good deal of time working towards the
restoration of our native plant diversity. High on my list of goals is
doing this is a hope of increasing the currently disappointing numbers and
diversity of bugs coming to lights at night. (At least the 10 lined June
Bugs/Beetles are still arriving at this time at the lights at Camp Long in
West Seattle) That said, I often wonder how much those lights themselves may
be leading to the decline of flying nocturnal insects. I often am amazed
that insects that navigate by moon or starlight and are attracted to lights
survive at all drowning in light in today's night-lighted skies in
frighteningly expanding metropolitan areas.

It seems that about 40 years ago it was common to turn off all lights at
night. Since then it has become the norm to leave lights on at almost every
business and quite a few homes. This has been a great loss both to the
insects and those of us that enjoyed the stars and having a real night time.
Though it would certainly be hard to quantify, I expect that these lights
have been an important factor in the decline of insects that fly at night
and are attracted to lights. The only night flying insect that comes to my
mind at this moment that is not attracted to light are mosquitos.

Let us not forget that the caterpillars that are the mainstay for songbird
nestling food are mostly nocturnal moths in the adult stage. These night
lights might well have been a factor in some songbird decline also.

Stewart Wechsler
Ecological Consulting
West Seattle
206 932-7225
ecostewart at quidnunc.net

-Advice on the most site-appropriate native plants
and how to enhance habitat for the maximum diversity
of plants and animals
-Educational programs, nature walks and field trips
-Botanical Surveys



-----Original Message-----
From: dennispaulson
Subject: [Tweeters] nighthawks and insect abundance


Hello, tweets.

In response to Wayne Weber's good post about Common Nighthawks, I wanted to
add that the species has also declined substantially in the East, where it
was a very common species until relatively recently. This is a bird that
winters in the Amazon Basin, and I wonder if there might be changes going on
down there that are causing a decline on the wintering grounds.

But I can also say something about the abundance of flying insects. When I
was a teen-ager and college student in Miami in the late 1950s and early
1960s, I started a collection of beetles, which grew into an obsession (all
collectors must suffer from OCD, or they aren't very successful). I was out
night after night visiting lights in shopping centers all over southern
Florida, eventually more widely in the Southeast. I gave the collection to a
museum when it totalled about 25 insect boxes stuffed full of beetles. There
were thousands (probably millions) of insects coming to lights everywhere I
went, from the tropical hammocks of the Keys to the edge of the Everglades
to the cypress swamps of north Florida. Anywhere I went, the sky was full of
flying insects around porch lights, street lights, and the high, bright
lights at shopping centers, parking lots, and freeways. These weren't all
microscopic; they included huge moths, giant water bugs, two-inch
long-horned beetles, al!
l kinds
of charismatic compound-eyed megainvertebrates.

In the same areas under the same circumstances now there are NO INSECTS
(statistically speaking). I have visited all parts of the Southeast over the
last three springs and summers. You can look up in the sky at night around
the lights at a shopping center anywhere now and see no more than a
desultory moth or two flying around the light, even when you are right next
to large tracts of pristine habitats. You can look outside your motel room
at the light on the wall in vain, even though a nice stand of woods is right
behind your motel. I used to find insects of all kinds at these lights,
often in sufficient numbers that getting into your room without bringing in
a whole heap of bugs was difficult.

I don't think the reason is because the lights have changed in wave length
or attractiveness, although I would be open to hearing that argument. An
exception to this was at Glenwood, Arkansas, this summer, where there were
quite a few insects at lights (this was at an entomological meeting, and
everyone at the motel was out late at night and early in the morning
photographing insects at each others' porch lights!), so I suspect their
absence in other areas is a real phenomenon. We all felt the hills of
Arkansas were remarkably rich in habitats and biodiversity, and
parenthetically, that would be a great state in which to live, even in the
absence of Ivory-billed Woodpeckers!

Obviously insects aren't absent from the Southeast and Northwest, as there
are still plenty of lizards, birds, bats, dragonflies, etc., in all these
areas that feed primarily on insects. But perhaps they are all less common
now! The change, as indicated by insects coming to lights, has been dramatic
and at least should be considered when noting the decline of birds such as
nighthawks.

This phenomenon has to be one of the most profound environmental changes
that has occurred in my lifetime, yet it has scarcely been mentioned in the
environmental literature. It should be front-page news. Silent Spring should
be rewritten as Empty Nights. Those of you who have lived in the Northwest
all your lives have no idea how abundant insects can be (or have been) in
the East and thus the degree of change that has taken place. If it has
happened here, it hasn't been obvious to me, just because I never saw that
many insects at lights to begin with when I arrived here 36 years ago. Some
of you may not know that the Pacific Northwest (westside) is the poorest
place in the Lower 48 for insects - probably why so many people like it
here!

Documenting such changes, at least anecdotally if not quantitatively, is one
of the reasons why we should keep naturalists around into their old age!

Dennis Paulson
1724 NE 98 ST.
Seattle, WA 98115
dennispaulson at comcast.net


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