 |
Protect Our
Woods
Working to preserve our rural heritage and quality of life in southern Indiana since 1985 |
Home Site Map Contact Us |
Home News & ALERTS Issues Forum Archives Conservationist's Alternative Klawitter Memorial Downloads Join Us About Us Contact Us Site Map Links |
ALERT - December 4, 2006: Protect Our Woods joins allies to submit a response to the Draft Supplement to the Final Environmental Impact Statement (FEIS) for the German Ridge Restoration Project in Hoosier National ForestPart 20c. Indiana bat (Part 3 of 5)Diversity of Roost Trees NeededFor example, notwithstanding the fact that the best science indicates that it is the microhabitat characteristics that spur the bats to choose their roosts, both primary and secondary, the impact analysis doesn’t mention anything about what those microhabitat characteristics might be that make a particular roost attractive to a particular bat or bats at a particular time. In spite of not addressing this key issue, the EIS makes sweeping statements about how their logging will not affect roosting. Yet, they don’t cite any authorities to back up this assertion. How can this be correct when the plan allows removal of trees that cannot be assured to not be roost trees for some Indiana bat during some part of their life cycle? Removing a roost tree would harm an individual or individuals of Indiana bats, because they are loyal to their habitat and return with a level of expectation of the habitat being essentially the same. As Edward Callahan, one of the leading Indiana bat researchers, wrote in his 1993 master’s thesis ("Indiana bat summer habitat requirements", University of Missouri, Columbia), “The greater number and larger diversity of roost trees that are now known to be utilized by Indiana bats expand the range and diversity of forest habitats that must be managed to protect and sustain maternal colonies.” Yet the Hoosier seems to think they can log and burn at will and it won’t change anything in regard to the Indiana bat. Smoke Can Harm Bats In addition, Lackey, a bat researcher from the University of Kentucky, found that smoke from fires can harm bats. In fact, the U.S. Fish and Wildlife Service has required incidental take statements for prescribed burning in bat habitat at certain times. Yet the DSEIS and FEIS’s ignore this and instead say that burning “may” improve Indiana bat habitat. This unsupported statement is just speculative and provides evidence of bias. Bats Prefer Closed Canopies In addition, as stated before, the Forest Service is overemphasizing openings in the forest as a benefit to Indiana bats in regard to their foraging preference. But this isn’t supported by scientific evidence. In fact, the whole analysis of the roosting habitat is shallow and with only handpicked references which seem to support the agency contention that they can log, burn, build roads, etc. and that there won’t be any kind of adverse impact to the bat or any other species. Heartwood did a much more thorough review of the literature of roosting habitat, and there has been more information since that time that supports Heartwood’s statement. Heartwood submitted it’s analysis of roosting habitat, which includes male roosting, which the Hoosier doesn’t seem to want to address (and how reproductive success can be addressed without considering male roosting habitat seems to be a serious question not answered by the planning documents), in response to the draft revised recovery plan. Heartwood’s statement included: “Roosting Habitat Indiana Bats roost in trees. This fact, as explained by Humphreys et al, makes the particular trees picked by the species critical to their survival: Reliance on tree nurseries, as described here, makes Myotis sodalis much more dependent on the vagaries of weather than if they occupied cave domes or buildings, although they still have the metabolic advantages of clustering. Accordingly, weather and roost temperature have important roles in the summer ecology of the species. The draft plan does provide the fundamental requirements of the species regarding roost trees, but again, downplays the importance of closed canopy forests in favor of open forests, in spite of contradictory scientific evidence, and underestimates the importance of large trees and ignores specific data on microclimate aspects which have been well documented. For example, the research is clearly indicating different roost sites for different seasons and for different weather conditions. The species obviously needs warmer sites in the fall and cooler sites in the summer. Yet, the plan attempts to paint a broad brush picture that the bats only like roost trees that are scattered, or in the open. This, according to the logic of the plan, means that logging is good for the bats. Yet, in Gardner, Garner, and Hofmann, “Summary of Myotis sodalis Summer Habitat Studies in Illinois: With Recommendations for Impact Assessment” they documented that out of 32 1/10 ha plots encircling Indiana bat roost trees, 22 were in closed canopy forests (80% or greater canopy closure)! Of those plots surrounded by closed canopy forest, the 14 plots in upland forest averaged 47 trees/acres greater than 11", and 125 trees/acre greater than 4". The 8 plots in floodplain forest averaged 61 trees/acre greater than 11", and 136 trees/acre greater than 4". Even those 10 roosts surrounded by “intermediate canopy closure,” 30 - 80% averaged 27 trees/acre greater than 11", and 145 trees/acre greater than 4". Clearly, this is not evidence that supports a finding that the species is a “savannah” species, or likes or requires an open forest. As Rommé et al found in their literature review, in total, Gardner and Garner found that 73% of 44 maternity roosts in areas with over 80% canopy, and 27% in areas 30-80% canopy. Rommé et al, in their habitat suitability model published in the same document, assumed that sites with 60 - 80% canopy cover were optimal for Indiana bat. According to Hobson in western Virginia, "Bat #458 roosted and foraged in George Washington National Forest until 20 May when the transmitter battery failed. For 19 nights, bat #458 roosted on a north facing slope (00 to 5" east of north) at 700 m elevation, beneath the bark of a mature shagbark hickory (ca. 30 in in height, 61 cm DBH). The bat roosted at a height >8 m in the shagbark hickory. Other tree species within a 10-in radius of the roost tree included basswood (Tilia americana), red maple (Acer rubrum), eastern hophornbeam (Ostrya virginiana), tulip poplar (Liriodendron fulipifera), and pignut hickory (Carya glabra).” Clearly this is not an “open canopy” situation either. When you add in the fact that the species prefers large trees, and requires a substantial number of larger snags, it is clear that the presence of scattered older, dead trees, is sufficient in and of itself to bring the canopy closure of a forest within the optimal range. It is only when no large trees are present, and the trees are densely packed would you ever have a 100% canopy cover, and that habitat is not preferred by the species. But any correlation between the habitat remaining after a commercial logging - be it even or uneven aged, and that habitat which has naturally evolved and created its own canopy gaps thru attrition, isn’t and cannot be based upon the best available science regarding the needs of the species. The USFWS is obviously ignoring the best science to further their goal to prevent the Indiana bat from becoming the spotted owl of the eastern United States. In fact, even Callahan’s paper, which did find a slight reduction in canopy closure between known roost sites and randomly chosen non-roost sites, still found that for primary snag roosts, which by nature exist in a reduced canopy due to their own loss of leaves, still existed in a 60% canopy cover, while live interior alternative roost trees existed in nearly a 70% canopy cover. These are not percentages that justify heavy handed logging to reduce significantly canopy cover! This was in a highly fragmented area of northern Missouri where most of the forest land were riparian strips along streams. This is also an area where the populations in the sharpest declines (i.e., Missouri Priority I hibernaculum) are likely summering. Clawson et al, in Indiana Bat Summer Habitat Patterns in Missouri (1996), found that canopy cover was not more dense or closed (nor any more open either) at sites where Indiana bats have been captured than at unsuccessful netting sites. However, the actual canopy cover figures were not supplied in the final paper. However, it is noteworthy that this paper did find a correlation between the presence of large trees and the netting of Indiana bats. Again, larger numbers of larger trees in a forest by nature indicates a denser canopy cover. Likewise, logging decreases the number of large trees. Even the courts have recognized the importance of closed canopy forests: M. sodalis is generally believed to require forest habitat with relatively complete canopy closure (Humphrey et al. 1977, Brack 1983). Capture data collected from 33 sites in Indiana (3D/ESI 1993) indicate that M. sodalis preferentially utilizes areas that include forest patches with relatively complete canopy closure (62.2 +/7.1%). House v. United States Forest Service, 974 F.Supp. 1022, 1031 (E.D.Ky. 1997). The draft plan states: Anecdotal evidence suggests that the Indiana bat may, in fact, respond positively to habitat disturbance. Indiana bats have been found roosting in shelterwood cuts in Kentucky (MacGregor, pers. observ. June 1997. We would first point out that this work was done in the fall, not the summer. It is much cooler in the fall than the summer, so bats would need warmer roosts in the fall. Additionally, there are many problems with the analysis. We would argue that finding the bats in the shelterwood cuts provide anecdotal evidence that logging harms the bats. Loyalty to habitat and roost trees can explain the bats roosting in the shelterwood cuts. MacGregor has acknowledged this: However, some of the appellants in the Heartwood regional bat habitat claim that this is merely because Indiana bats were so loyal to traditional roosting areas that they have continued to use them even when habitat has become severely degraded. It is difficult to entirely dismiss this alternative interpretation since we have no data on where many of these bats roosted prior to timber harvest (such data would be impossible to obtain, of course). Report to the Daniel Boone National Forest Management Team; Indiana Bat Roost Tree Use Monitoring - 1996-97 Summary, March 1999. The unpublished analysis MacGregor has done which shows the Indiana bat using shelterwood cuts more than expected is fatally flawed. First, as mentioned above, loyalty to habitat can explain the results (and he has documented loyalty to trees and the area). More importantly, his analysis fails to take into account the fact that all the logging was in the areas the bats prefer for roosting. All but one of the bats was roosting on or near the ridge tops. And all the logging was on the ridge tops. MacGregor’s analysis assumed that the probability of the bats roosting on ridge top was the same as it roosting in a valley. Since the bats were not roosting in the valleys and all the logging was on the ridge tops, it significantly skews the analysis and makes the results inaccurate. MacGregor needs to either exclude the valleys from his analysis or statistically take into account the fact that they do not roost in the valleys. MacGregor’s data also found that half the bat roosts days were in forests with 80% or more canopy closure. His results for 1997 were as follows: Canopy Closure Bat Days <60% 34 60-80% 27 >80% 61 More specifically: Habitat Canopy Closure Bat Days Percent use 2-age Shelterwood Cuts/Highgrades 20-81% 36 28.8% Red-cockaded Woodpecker Rx Burns 24-71% 6 4.8% Natural Canopy Gaps (Storm Damage) 24-88% 23 18.4% Edges of Woods Roads and Gravel Roads 80-90% 5 4.0% General Closed Gap Canopy Forest 79-93% 55 44.0% In spite of this being in the fall, most of the bats days were in a closed canopy forest or natural canopy gap. But a study in the Shawnee by Feldhamer and Carter indicated that there was no statistical difference in canopy cover between roost trees and randomly selected non roost trees in the territory of a maternity colony. Therefore it is likely that the alteration of microhabitats around roost trees will cause degradation of used habitat. Click here for Part 20d. Indiana bat (Part 4 of 5)Protect Our Woods
PO Box 352 Paoli, Indiana 47454 |