Text Only Version

Firefly Safe Zones: Strategies for Reintroduction, Preservation and Maintenance of Vigorous Firefly Populations
By Terry Lynch, 26 Dec. 2000

The process of urbanization results in the destruction of that habitat most suitable for fireflies. This may be attributed to the fact that firefly larvae live in either leaf litter (Photurids), the upper layer of soil (Photinids) or wetlands (Pyractomids). It follows that any development which destroys the natural habitat of firefly larvae will soon result in the disappearance of adult fireflies, especially where there are factors introduced which target adult insects and/or their larvae for eradication.

The first step in preserving firefly populations is to reverse the process of urbanization, designing communities which tend toward preserving forest and meadows. This involves a primary change in the consciousness of people, especially land usage planners, contractors and developers. A religious metamorphosis of sorts in this respect is needed, such that people in general will be more reverent toward our natural environment than toward the artificial environs of immaculately kept lawns, treeless neighborhoods and asphalt shopping centers.

Since this enlightenment isn't likely to happen any time soon, perhaps the most we can hope for is to establish parks and preserves such that every community will have a relatively large area set aside to remain forever in its natural state. This means no paved roads, no street lights, no bug zappers and absolutely no spraying of insecticides or herbicides in preserve areas. Not only will this benefit fireflies, it will benefit all flora and fauna indigenous to an area. Generally what is good for fireflies will be good for people so this represents no sacrifice except to that discourageable suburbanite who think , "the only good bug is a dead bug."

This brings up an interesting point. In order to achieve any real reform and enduring preservation of our environment, it is necessary to educate our children and their parents to have a reverence for nature. One way to do this s to teach our children not just reading, writing and arithmetic, but how to be young naturalists. I suggest that every school, public and private alike, teach the natural sciences from kindergarten through high school, that the natural sciences be a part of every K-12 private and public education program. In fact it may be found that if we teach our children how to study animals and plants, how to be young naturalists, that this will carry over to their parents, such that our society gradually has as much respect for insects, spiders, snakes and other small animals as they do for ethereal gods!

I would also suggest that instead of presidents, we put beetles, butterflies and birds upon our currency, not as patriotic symbols, but as wonders of nature in their own right. Then if we pour some of this redesigned currency into programs designed to preserve our environment, maybe fireflies will begin to make a come back in areas where they have disappeared.

Toward that end we may take knowledge we have about the life cycle of fireflies and endeavor to reduce all factors which may stress firefly populations. I believe that would include not spraying entire communities for mosquitos during the periods that fireflies are active. It would certainly mean outlawing bug zappers from residential areas which kill as many beneficial insects as they do pest insects. In may also mean removing street lights form our communities, that we reduce crime not by lighting up our neighborhoods but by endeavoring to create a society which abhors the idea of being criminal in nature and is not afraid of the dark.

This should be no more difficult or expensive than special projects to reintroduce fireflies to areas where they have disappeared. Some such environmental hazard zones, from the view point of fireflies :-) would require complete demolition of all human intra structure, including roads, parking lots and buildings, replacing them with planned, carefully landscaped communities which incorporate trees and forests back into the landscape. It may even be necessary to truck in large amounts of top soil preferably from areas being more properly developed in an effort to reestablish other areas. To some degree such soil may even help reintroduce fireflies, given that firefly larvae may be contained in top soil. In other words, with proper land usage management, firefly and human habitats may be compatible.

Other measures may include establishment of firefly raring programs. To enjoy some degree of success such efforts would need to be well funded and should be directed at creating entire nature preserves, given that fireflies are most likely to survive in preserve or park type areas which have as little unnatural development as possible. I have related sufficient information about the rearing of fireflies in the Firefly Notebooks at http://home.att.net/~y2kvault/firefly_notebooks.html and if this information and suggested techniques were used as a guide, a concerted, well funded effort should enable the establishment and maintenance of firefly safe zones as preserves.

In fact people living in areas where fireflies occur should consider establishing firefly safe zones. These are preserve or park areas where no shot gun application of pesticides will be made, such as in the spraying for mosquitoes by truck which drive through neighboorhoods at twilight during the times when adult fireflies are active. Also natural landscape, vegetation and soil conditions will be maintained. If every city has firefly safe zones, nature preserves which include consideration for all animal and plant species, then fireflies and other endangered or threatened species of small animals will have an increased chance of survival.

The type of development which should be discouraged is that where landscape rapers go into a firefly habitat or wet land, clear cut the forest destroying all trees, plow up the top soil to completely disturb and destroy the cryptosphere (that upper layer of leaf litter and soil where firefly larvae develop) and then top it off with asphalt. A better way to develop land is to use a lattice type of landscaping which preserves as many trees as possible, only removes trees where buildings will be placed and limits paving to one way, one lane, streets or bicycle paths with limited parking or access to the area via subway, elevated rail or trolley.

It may be unrealistic to expect developers to endeavor to preserve the environment when building housing areas, shopping centers, malls or other commercial or residential projects. But unless we start doing this, many small animal habitats will be forever lost to the bulldozer. As a consequence not only will fireflies disappear, but countless other species which people do not notice will vanish. We notice the disappearance of fireflies because healthy populations blink, glow and advertise themselves during their summer mating flights. Hence the flashing of fireflies is an indicator that our environment is healthy. When fireflies begin to flash no more during early spring and summer months it is a warning signal that we are doing something wrong to our environment. Unless we take notice and correct our actions, unless we stop raping our environment, fireflies and many other small animals may forever vanish from the face of the earth! That will not be good either for fireflies or human beings for a world without fireflies will ultimately be less habitable and less enjoyable for human beings!

ADDENDUM: 7 Jan. 2001 - With regard to this issue it occurred to me that as young Photinid larvae tend to resemble fragments of brown pine needles, and as this may be a method of protective resemblance for these firefly larvae, that any preservation efforts should include maintaining pine forest areas. In fact it may be that Photinid in North America survive best in pine forest areas because of the role protective resemblance to pine needles fragments plays in survival of firefly larvae. Hence when trying to preerve a species like P. Pyralis it would be wise to provide a top soil rich in organic debris which includes an abundance of decaying pine needles. In fact one might question the role pine trees and pine needle litter plays in creating a top soil that is the proper consistency, pH, etc., for firefly larvae of the Photinid variety. I would suspect that it may be found these larvae only or most readily inhabit soils conditioned by pine trees and/or the degeneration of pine needles.

Conclusion

I would suspect Photinid are not likely to occur in areas where there are not pine tree forests as the larvae have evolved to protectively resemble pine needles and this must play a vital role in their survival. This could be because pine tree forest produce all the conditions most suitable for these fireflies to survive, including such factors as shade, correct amount of soil moisture, proper soil consistency, a rich supply of earth worms, and other factors most likely to result in healthy firefly populations. Areas where pine tree forest do not occur are more arid, have less organic matter in the soil, do not support earthworm populations which feed upon decaying vegetation, and hence, firefly larvae can not survive and thrive in such soils. This is the primary reason fireflies are not readily seen or do not occur in may habitats west of the Mississippi River or in many regions of North America which do not have pine tree forest to properly condition the soil and create the type of soil environment conducive to the survival of Photinids.

If firefly safe zones are to be created, especially with respect to the preservation of various species of Photinids, pine forest must be preserved and maintained. In areas which have been logged or deforested, it is vital that pine trees be replanted and that areas not all be cut at the same time, such that there be adjoining areas of established pine tree forest which allow for the reintroduction of species to areas where new pine trees are planted. This is much the same process nature uses when there is a fire. Fires generally burn an area in a random, puzzle like pattern, such that when new growth occurs in the burnt area, animals and plants from the unburned area are reintroduced via seedlings and migration. Thus to preserve firefly populations, especially Photinids, it is necessary that we manage pine forests such that there always be uncut, established, older forests, mixed and mingled with deforested areas.

In a like manner when communities are planned, pine forests should be maintained. This means replanting pine tree and making pine trees a part of landscaping projects. If communities will retain their pine forest it is highly probably that Photinid firefly population will remain healthy. The same is true of other varieties of fireflies such that if their habitat is preserved, they will remain healthy. It is highly recommended that neighborhoods where firefly populations (Photinids) have disappeared, immediately undertake reforestation efforts, such that all yards have pine trees planted and that pine needles be incorporated into the soil so that they may regenerate the proper soil conditions for firefly larvae. Doing this (planting pine trees or failing to plant pine trees) may have a greater impact upon survival of Photinid fireflies in developed areas than any other single action people may make.

Questions for further study:

1. With respect to pine forest and hardwood forests, and forest in transition form pine forest to hardwood forest, how do firefly populations vary? One might suspect based upon the fact that Photinid may readily occur and be collected in pine forest areas, that soil rich in decaying pine needles contributes to the survival of larvae. I hypothesize that a major factor in the survival of Photinid larvae is that their long bodies tanned to resemble the color of decaying pine needles indeed contributes to the survival of these larvae. I have noticed in collecting Photinid that these larvae are difficult to spot because they resemble a fragment of a decaying pine needle, in both color and markings that it appears Photinid larvae protectively resemble pine needles. This may be illustrated by color photography of Photinid larvae against the pine needle rich soil litter in which they occur.

2. Do Photurid larvae occur more readily in pine forest or hardwood forests? Note the resemblance of Photurid larvae to leaf litter typical of hardwood forest areas. In fact Photurid larvae are broad and flat to make them resemble decaying leaves rather than pine needles. Hence one may suspect that this protective resemblance of decaying leaves contributes to the survival of Photinid larvae and is in keeping with the fact these larvae may be most abundant in hardwood forest or in forest which are in transition between a pine forest and hardwood forest. Of course it is my experience that pine forest generally have a plenty of leaf litter, given a variety of hardwood trees tend to also occur in pine forests. Therefore it may just be that Photurid protectively resemble leaves as they inhabit the upper layer of leaf litter rich soils, while Photinid protectively resemble pine needles as they inhabit a lower layer of soil typical of broken decaying pine needles which tend to filter down beneath the larger leaves of the upper layer of the cryptosphere.

3. Make a comprehensive study which will corelate the nature of soil in speicfic areas to the speices of fireflies and firefly larvae occuring in that area. Record the type, range and variety of small animals occurring in the soil as via use of Berlese funnel collections. Record and describe the appearence and nature of the soil, taking samples, viewing these under a microscope and making photographs of the soil. Also have each soil sample analysed to determine its pH and moisture content. Also try to determain the nature of organic content as to whether this is due to pine needle fragments or leaf litter debris. Other soil factors may be included. Also one may want to determine the soil's salt or other mineral content if this is a factor. What soils retain heat and/or water the best? Are there any relationships between soil types whare Photinid occur and where they have never been observed?

4. If protective resemblence to pine needle fragments contributes to the survival of Photinid larvae, what is the primary firefly larvae prey or prey animals which is involved in this relationship? Does the fact Photinid larvae resemble pine needle fragements protect the larvae from ants? Is this why in areas which may not have pine trees and which have fireants, that Photinids more readily disappear? It may be possible to investigate this by offering Photinid larvae to fireants in soils that contain pine needles and in soil that does not contain pine needles. I would hypothesize that fireants more readily detect firefly larvae in soils which do not contain pine needles should ants be the primary predator of Photinid larvae which are deterred from finding the firefly larvae by a substrate rich in pine needles. This would probably be because the fireants would have a problem detecting the difference between a Photinid larvae and pine needle fragments, where as if there are no pine needle fragments, a Photinid larvae would stand out as a different shape and so be easily detected as a prey animal. Of course because imported fireants do not naturally occur in North America and are an introduced species this protective resemblence to pine needles may relate to the presence of other natural Photinid larvae predators. This may be due to natural varieties of fireants or other species of ants or it may involve predation by spiders, cenipedes or other small predacious animals in the cryptosphere. It may even be Photurid larvae which which Photinid is being protected from by this protective resemblence.

It would be easy enough to see what difficulty Photurid larvae has in locating and preying upon Photinid larvae. Simply place Photinid and Photurid larvae in the same containers, one with just a clay or sandy soil free of pine needle fragments, and other containers with progrogressively more pine needle fragments. Observe to see if Photurid larvae prey upon Photinid larvae, and if the presence of pine needle fragments reduces the occurrence of this predation as I suspect it would. If this proves to be the case it will be interesting as it will show that where as Photinid larvae have evolved to evade predation from Photurid larvae, given Photinid protectively resemble pine needle fragment and inhabit that layer of soil rich in pine needles, Photinid adults still fall prey to Photuris adults which have learned to mimic the blink responses of females Photinids so as to attract and devour males lured by this aggressive mimicry.

Other Lynch Sites>

Project K9

| Blinks and Links

| Bioluminescence in Fireflies: The luciferase-luciferin reaction in Photinus pyralis

| Part I: Application of Torque to Induce Simultaneous Flight Response and Synchrony in Drosophila

| The Amateur Naturalist

| Firefly Notebooks

| Contact the author

Copyright 2001 by Terry Lynch . All Rights Reserved.

mail comments to burger@burger.com

[Go Back to My Firefly Page]

[Go Back to My Home Page]