karner blue

[Mark Walker]

Michael,

What is the significance of the Pine/Oak barren habitat?  I'm fairly certain
that L. perennis is not specific to this habitat, and that the Lupine can be
found throughout northern New England (very local, and not widespread as
you've mentioned - and disappearing).  Yet, to my knowledge, the butterfly
is only found in the sandy barren types of habitats.  Maybe it has something
to do with the overwintering ova.  I hadn't heard that explanation before,
but it makes good sense.  This might also explain why the butterfly
disappeared first from it's southernmost locations.

Mark Walker.

> -----Original Message-----
> From:	Michael Gochfeld [SMTP:gochfeld at EOHSI.RUTGERS.EDU]
> Sent:	Saturday, February 06, 1999 5:47 PM
> To:	leps-l at lists.yale.edu
> Subject:	Re: karner blue
> 
> The larval host, Lupinus perennis, is not that widespread, and it is 
> declining in certain areas of the Albany Pine Barrens.  One of the 
> central areas where I used to find both Lupine and Karner Blue, is now 
> almost completely devoid of both, although a few plants are growing 
> among the grasses near a parking lot.  There are some experimental areas 
> with exclosures designed to protect the lupine from grazing by deer. On 
> two visits to this experimental site in 1997 and 1998, it didn't look 
> like the Lupines were doing worse outside the exclosures than inside 
> them. 
> 
> One of the reasons for the decline of the Lupine in the central area, is 
> probably succession due to fire suppression. However, I suspect that the 
> burgeoning deer population may contribute to its decline in some areas 
> (my garden for example). 
> 
> Controlled burning would probably help the Lupine. Whether it would help 
> the butterfly is another story.  One possibility is that after years of 
> fire suppression you get a build up of litter so that the next fire that 
> eventually does come through is much hotter, and kills lots of things 
> that would have otherwise survived---perhaps the ants are in this 
> category. 
> 
> However, there are several species of ants that tend Karner Blue 
> caterpillars, and although the tended caterpillars have about twice the 
> survival rate of untended ones (based on work by  Dolores Savignano 
> who did a study of the Karner Blue and its ant associates in the Albany 
> Pine Bush) ants are apparently not essential for individual survival. 
> 	
> Another suggestion is that a series of warm winters with scant snow 
> cover is at fault.  The Karner Blue---at least at Albany---overwinters 
> in the egg stage, and itis possible that with inadequate snow cover the 
> eggs desicate or otherwise succumb. Normally the eggs hatch in mid-April 
> about the time that new shoots of Lupine appear. 
> 
> It's also obvious that many other Lycaenids are in trouble. The 
> International Union for the Conservation of Nature has published an 
> entire volume (edited by T.R. New, 1993) on "Conservation Biology of 
> Lycaenidae (Buterflies). 
> 
> The research on this species has been done mainly by Cryan and Dirig and 
> their students. These authors reported that between mid 1970's and 1989, 
> Lupine had disappeared from 18 or 46 of their study sites, and many of 
> the persisting stands had declined due to shading.
> 
> Although all of these factors may interact, I think that controlled 
> burning is critical to survival of the species, although it will not be 
> popular since the Pine Bush has become a mosaic of habitat fragments 
> with residential and commercial properties interspersed. And, of course, 
> development pressure continues to mount.   
> 
> M. Gochfeld