by Lynne Jackson
ALBANY: Neil Gifford, Conservation Director of the Albany Pine Bush Preserve Commission shared hopeful news with Save the Pine Bush at the October veggie/vegan lasagna dinner.
The Karner Blue butterfly feeds on wild blue lupine. There are two broods a year, the first brood comes out in late May/early June, and the second in July. The butterflies come out, lay eggs. Those eggs become butterflies which come out in July, at which point, the cycle starts all over again, with the eggs wintering over.
The Karner Blue butterfly is in range-wide decline — over 90% decline since the 1970s.
Currently the only large, healthy populations of Karner Blue are in Wisconsin and Michigan. New Hampshire lost their butterflies in 2000 and people are currently working to reintroduce the butterflies in Concord, using butterflies from Glacial Lake Albany. Glacial Lake Albany is very important to the ecology and recovery of the Karner Blue butterfly. It is the eastern stronghold for the species. Karner Blues are also being reintroduced in Ohio and Illinois.
The Federal Recovery Plan adopted in 2003 for the Karner Blue outlines recovery goals for the butterfly. Fourteen recovery units have been identified across the range of the species. Within Glacial Lake Albany, there are four populations left: the Albany Pine Bush, Saratoga West (the Saratoga Airport), Saratoga sand plains, (up in Wilton and Milton, which most closely represents the population of butterflies in New York and how they used to behaved naturally) and the Queesnbury sand plains. All of the populations are very small, with 20-30 butterflies, with the biggest population having a couple of hundred of butterflies.
The Federal Plan states that three of these four areas must be fully recovered for the butterfly to be de-listed as an endangered species. The State draft Karner Blue Recovery plan calls for the recovery of all four sites.
Neil Gifford briefly mentioned Karners that have been found in Clifton Park. Pointing to a map, he noted that there is a big gap between the Albany Pine Bush and the Saratoga County sites. There are a couple of known sites in the Clifton Park area and a lot of sand in Clifton Park. Undoubtedly the Karner Blue once covered that area. The Commission believes that in the future, this link, through Clifton Park, may need to be re-built.
The Federal Recovery Plan outlines what the goal is for the butterfly to be considered recovered. Two types of populations are defined for the butterfly: viable populations and large viable populations. For the species to be de-listed, there are different requirements in Michigan and Wisconsin than there are in New York. Michigan and Wisconsin require large viable populations. In New York, to be de-listed, the Karner Blue needs to have three viable populations.
What is the difference between a “viable population” and a “large viable population”? To be considered a viable population, there must be at least 3000 butterflies for either the spring or summer broods for four out of five consecutive years. The fifth year, there must be at least 3000 butterflies, and during no year can the count drop below 1500. Large viable populations are required for the butterfly to be de-listed in Michigan and Wisconsin.
For a viable population in New York, we need a management plan approved by the Fish and Wildlife Service that provides for suitable buffering in case of adverse events. For example, two or three years in a row of very dry or very wet weather could wipe out a population. These types of events have happened in the past in New York and have decimated the butterflies across the state. Another requirement is for the maintenance of a successional array of suitable habitat. The butterfly needs ecosystems from the very early successional open pine barrens to more closed-canopy pine-oak woodlands. The Pine Bush is an early-successional plant community that is maintained by wildfires. Without fire, the ecosystem will turn into something else.
One of the biggest challenges in the Pine Bush is connectivity. The typical Karner Blue butterfly will only travel 200 yards in its short five-day lifetime as an adult butterfly. Two to ten per cent of the butterflies have the gene to wander and disperse and go much farther than that. Typically, these butterflies will not travel more than one or two kilometers. A sub-population can only be considered viable if it is connected to at least two other sub-populations.
A “large viable population” occupies more land has to contain 10 square miles (6,400) acres. Ten percent or 640 acres must be occupied Karner Blue habitat. These 640 acres needs to be dispersed over two-thirds of the entire 6,400 acres. In addition, a large viable population needs a minimum of 6,000 butterflies, not three thousand. The reason for the additional butterflies is there is a huge cost involved with having to manage and monitor butterflies across ten square miles for a preserve of 3000 butterflies. The idea is that if you have more land preserved, it should cost less to monitor and manage it. However, with more butterflies, you can spend less to monitor them. In Wisconsin, the Karner Blue populations are in the tens of thousands of butterflies.
What is a meta population? Karner Blues exists in a large landscape. The butterflies are not necessarily everywhere, but exist in isolated pockets that are connected. The butterflies are constantly moving between these pockets. Its not that you have 10,000 acres of butterfly habitat, you have patches of habitat across 10,000 acres. Each patch, or sub-population, needs to be connected to at least two other sub-populations. That is in case of a bad weather event or a fire goes through the area, each patch can be re-colonized by at least two potential sources. Connectivity — the ability of the butterflies to get from one sub-population to another — is critical. All of these sub-populations together make up one meta-population.
To Be Continued . . . In the April/May issue of the Save the Pine Bush newsletter, this article will be continued, and the Commission’s Karner Blue strategy will be described.