Je veux savoir à propos de…

jbell on DSKJLSW7X2PROD with PROPOSALS3

29452

Federal Register / Vol. 86, No. 103 / Tuesday, June 1, 2021 / Proposed Rules
displays because of the reduction in structure from formerly dense vegetation Cannon and Knopf 1979, entire.
More recently, research evaluating indirect effects concluded that prescribed fire and managed grazing following the patch-burn or pyric herbivory grazing practices shaped fire approach will benefit lesser prairiechicken through increases in forbs;
invertebrates; and the quality, amount, and juxtaposition of brood habitat to available nesting habitat Elmore et al.
2017, entire. The importance of temporal and spatial heterogeneity derived from pyric herbivory is apparent in the female lesser prairiechicken use of all patch types in the patch-burn grazing mosaic, including greater than 2 years post-fire for nesting, 2-year post fire during spring lekking, 1- and 2-year post-fire during summer brooding, and 1-year post-fire during nonbreeding season Lautenbach 2017, pp. 2022. While the use of prescribed fire as a tool for managing grasslands throughout the lesser prairie-chicken range is encouraged, current use is at a temporal frequency and spatial extent insufficient to support large amount of lesser prairie-chicken habitat. These fire management efforts are limited to a small number of fire-minded landowners, resulting in effects to a small percentage of the lesser prairiechicken range.
While lesser prairie-chicken evolved in a fire-adapted landscape, little research Thacker and Twidwell 2014, entire has been conducted on response of lesser prairie-chicken to altered fire regimes. Research to date has focused on site-specific responses and consequences. Human suppression of wildfire and the limited extent of fire use prescribed fire for management over the past century has altered the frequency, scale, and intensity of fire occurrence in lesser prairie-chicken habitat. These changes in fire parameters have happened simultaneously with habitat loss and fragmentation, resulting in patchy distribution of lesser prairie-chicken throughout their range. An increase in size, intensity, or severity of wildfires as compared to historical occurrences results in increased vulnerability of isolated, smaller lesser prairie-chicken populations. Both woody plant encroachment and drought are additive factors that increase risk of negative consequences of wildfire ignition, as well as extended post-fire lesser prairiechicken habitat effects. The extent of these negative impacts can be significantly altered by precipitation patterns following the occurrence of the
VerDate Sep<11>2014

20:04 May 28, 2021

Jkt 253001

fire; dry periods will inhibit or extend plant community response.
Historically, fire served an important role in maintenance and quality of habitat for the lesser prairie-chicken.
Currently, due to a significant shift in fire regimes in the lesser prairie-chicken range, fire use for management of grasslands plays a locally important but overall limited role in most lesser prairie-chicken habitat. This current lack of prescribed fire use in the range of the lesser prairie-chicken is contributing to woody plant encroachment and degradation of grassland quality due to its decoupling from the grazing and fire interaction that is the foundation for plant community diversity in structure and composition, which in turn supports the diverse habitat needs of lesser prairie-chicken.
These cascading effects contribute to greater wildfire risk, and concerns exist regarding the changing patterns of wildfires scale, intensity, and frequency and their consequences for remaining lesser prairie-chicken populations and habitat that are increasingly fragmented. Concurrently, wildfire has increased as a threat rangewide due to compounding influences of increased size and severity of wildfires and the potential consequences to remaining isolated and fragmented lesser prairie-chicken populations.
Extreme Weather Events Weather-related events such as drought, snow, and hail storms can influence habitat quality or result in direct mortality of lesser prairiechickens. Although hail storms typically only have a localized effect, the effects of snow storms and drought can often be more widespread and can affect considerable portions of the lesser prairie-chicken range. Drought is considered a universal ecological driver across the Great Plains Knopf 1996, p.
147. Annual precipitation within the Great Plains is highly variable Wiens 1974, p. 391, with prolonged drought capable of causing local extinctions of annual forbs and grasses within stands of perennial species; recolonization is often slow Tilman and El Haddi 1992, p. 263. Grassland bird species in particular are impacted by climate extremes such as extended drought, which acts as a bottleneck that allows only a limited number of individuals to survive through the relatively harsh conditions Wiens 1974, pp. 388, 397;
Zimmerman 1992, p. 92. Drought also interacts with many of the other threats impacting the lesser prairie-chicken and its habitat, such as amplifying the
PO 00000

Frm 00022

Fmt 4701

Sfmt 4702

effects of incompatible grazing and predation.
Although the lesser prairie-chicken has adapted to drought as a component of its environment, drought and the accompanying harsh, fluctuating conditions high temperatures and low food and cover availability have influenced lesser prairie-chicken populations. Widespread periods of drought commonly result in bust years of recruitment. Following extreme droughts of the 1930s, 1950s, 1970s, and 1990s, lesser prairie-chicken population levels declined and a decrease in their overall range was observed Lee 1950, p. 475; Ligon 1953, p. 1; Schwilling 1955, pp. 56;
Hamerstrom and Hamerstrom 1961, p.
289; Copelin 1963, p. 49; Crawford 1980, pp. 25; Massey 2001, pp. 5, 12;
Hagen and Giesen 2005, unpaginated.
Additionally, lesser prairie-chicken populations reached near record lows during and after the more recent drought of 2011 to 2013 McDonald et al. 2017, p. 12; Fritts et al. 2018, entire.
Drought impacts prairie grouse, such as lesser prairie-chicken, through several mechanisms. Drought affects seasonal growth of vegetation necessary to provide suitable nesting and roosting cover, food, and opportunity for escape from predators Copelin 1963, pp. 37, 42; Merchant 1982, pp. 19, 25, 51;
Applegate and Riley 1998, p. 15;
Peterson and Silvy 1994, p. 228;
Morrow et al. 1996, pp. 596597; Ross et al. 2016a, entire. Lesser prairiechicken home ranges will temporarily expand during drought years Copelin 1963, p. 37; Merchant 1982, p. 39 to compensate for scarcity in available resources. During these periods, the adult birds expend more energy searching for food and tend to move into areas with limited cover in order to forage, leaving them more vulnerable to predation and heat stress Merchant 1982, pp. 3435; Flanders-Wanner et al.
2004, p. 31. Chick survival and recruitment may also be depressed by drought Merchant 1982, pp. 4348;
Morrow et al. 1996, p. 597; Giesen 1998, p. 11; Massey 2001, p. 12, which likely affects population trends more than annual changes in adult survival Hagen 2003, pp. 176177. Drought-induced mechanisms affecting recruitment include decreased physiological condition of breeding females Merchant 1982, p. 45; heat stress and water loss of chicks Merchant 1982, p. 46; and effects to hatch success and juvenile survival due to changes in microclimate, temperature, and humidity Patten et al.
2005, pp. 12741275; Bell 2005, pp. 20
21; Boal et al. 2010, p. 11. Precipitation, or lack thereof, appears to affect lesser
E:FRFM01JNP3.SGM

01JNP3