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Diurnal Habitat Selection Of Migrating Whooping Crane In The Great Plains, David M. Baasch, Patrick D. Farrell, Aaron T. Pearse, David A. Brandt, Andrew J. Caven, Mary J. Harner, Greg D. Wright, Kristine L. Metzger

USGS Northern Prairie Wildlife Research Center

Available stopover habitats with quality foraging opportunities are essential for migrating waterbirds, including Whooping Crane (Grus americana). Several studies have evaluated habitats used by Whooping Crane for roosting throughout its migration corridor; however, habitats associated with foraging and other diurnal activities have received less attention. We used data collected from 42 Whooping Crane individuals that included 2169 diurnal use locations within 395 stopover sites evaluated during spring 2013 to fall 2015 to assess diurnal habitat selection throughout the U.S. portion of the migration corridor. We found that Whooping Crane selected wetland land-cover types (i.e., open water, riverine, and semipermanent wetlands) …

An Unparalleled Opportunity For An Important Ecological Study, L. David Mech, Shannon M. Barber-Meyer, Juan Carlos Blanco, Luigi Boitani, Ludwig Carbyn, Glenn Delgiudice, Steven H. Fritts, Djuro Huber, Olof Liberg, Brent Patterson, Richard R. Thiel

USGS Northern Prairie Wildlife Research Center

Wolves (Canis lupus) and moose (Alces americanus) have been studied since 1958 on 540-squarekilometer Isle Royale National Park, in Lake Superior. Wolves arrived there across the ice around 1949, and the population once increased to about 50, averaging about 25 annually (Mech 1966, Jordan et al. 1967, Vucetich and Peterson 2009). However, for various reasons, wolf numbers there have now dwindled to 2 nonbreeders, and the US National Park Service has proposed reintroducing 20–30 wolves over 3 years (National Park Service 2016). This situation offers an unparalleled opportunity to promote science-based management of this unique national park. …

Sandhill Crane Roost Selection, Human Disturbance, And Forage Resources, Aaron T. Pearse, Gary L. Krapu, David A. Brandt

USGS Northern Prairie Wildlife Research Center

Sites used for roosting represent a key habitat requirement for many species of birds because availability and quality of roost sites can influence individual fitness. Birds select roost sites based on numerous factors, requirements, and motivations, and selection of roosts can be dynamic in time and space because of various ecological and environmental influences. For sandhill cranes (Antigone canadensis) at their main spring staging area along the Platte River in south-central Nebraska, USA, past investigations of roosting cranes focuse donphysical channel characteristics related to perceived security as motivating roost distribution.We used 6,310 roost sites selected by 313 sandhill cranes over …

Patuxent’S Long-Term Research On Wolves, L. David Mech

USGS Northern Prairie Wildlife Research Center

The gray wolf (Canis lupus) was one of the first species placed on the Endangered Species List in 1967. The Endangered Species Act of 1973 legally protected the wolf along with other listed species.

Patuxent Wildlife Research Center (Patuxent) in Laurel, MD, began its Endangered Wildlife Program in 1966, and U.S. Fish and Wildlife Service (USFWS) biologist Ray Erickson was assigned to lead it. In 1973, I was transferred to the program from Region 3 of the USFWS, having been employed there since 1969 to study wolves in Minnesota.

Endangered Species Act protection of the wolf fostered its quick …

Use Of Cranial Characters In Taxonomy Of The Minnesota Wolf (Canis Sp.), L. David Mech, Ronald M. Nowak, Sanford Weisberg

USGS Northern Prairie Wildlife Research Center

Minnesota wolves (Canis sp.) sometimes are reported to have affinity to a small, narrow-skulled eastern form (Canis lupus lycaon Schreber, 1775) and sometimes to a larger, broader western form (Canis lupus nubilus Say, 1823). We found that pre-1950 Minnesota wolf skulls were similar in size to those of wolves from southeastern Ontario and smaller than those of western wolves. However, Minnesota wolf skulls during 1970–1976 showed a shift to the larger, western form. Although Minnesota skull measurements after 1976 were unavailable, rostral ratios from 1969 through 1999 were consistent with hybridization between the smaller eastern wolf and …

Infectious Diseases In Yellowstone’S Canid Community, Emily S. Almberg, Paul C. Cross, L. David Mech, Doug W. Smith, Jennifer W. Sheldon, Robert L. Crabtree

USGS Northern Prairie Wildlife Research Center

Each summer Yellowstone Wolf Project staff visit den sites to monitor the success of wolf reproduction and pup rearing behavior. For the purposes of wolf monitoring, Yellowstone National Park (YNP) is divided into two study areas, the northern range and the interior, each distinguished by their ecological and physiographical differences. The 1,000 square kilometer northern range, characterized by lower elevations (1,500–2,200 m), serves as prime winter habitat for ungulates and supports a higher density of wolves than the interior (20–99 wolves/1,000 km² versus 2–11 wolves/1,000 km²). The interior of the park encompasses 7,991 square kilometers, is higher …

What Is The Taxonomic Identity Of Minnesota Wolves?, L. David Mech

USGS Northern Prairie Wildlife Research Center

The taxonomic identity of the historical and current wolf (Canis lupus L., 1758 or Canis lycaon Schreber, 1775 or their hybrids) population in Minnesota (MN) and the Great Lakes region has been, and continues to be, controversial. So too does its legal status under the U.S. Endangered Species Act. This review summarizes the morphological and genetic information about that population and concludes that historically the MN population consisted of a gray wolf (C. lupus) in the west and an eastern type (Canis lupus lycaon or C. lycaon) in the east with intergrades or hybrids between …

Wolf Body Mass Cline Across Minnesota Related To Taxonomy?, L. David Mech, William J. Paul

USGS Northern Prairie Wildlife Research Center

Recent genetic studies suggest that in northern Minnesota two species of wolves (Canis lupus L., 1758 or western wolf and Canis lycaon Schreber, 1775 (= Canis rufus Audubon and Bachman, 1851) or eastern wolf) meet and hybridize. However, little morphological information is available about these two types of wolves in Minnesota. We analyzed the mass of 950 female wolves and 1006 males older than 1 year from across northern Minnesota and found that it increased from 26.30 ± 0.56 kg (mean ± SE) for females and 30.60 ± 0.72 kg for males in northeastern Minnesota to 30.01 ± 0.43 …

Factors Influencing Predation On Juvenile Ungulates And Natural Selection Implications, S. M. Barber-Meyer, L. D. Mech

USGS Northern Prairie Wildlife Research Center

Juvenile ungulates are generally more vulnerable to predation than are adult ungulates other than senescent individuals, not only because of their relative youth, fragility, and inexperience, but also because of congenital factors. Linnell et al.’s (Wildl. Biol. 1: 209-223) extensive review of predation on juvenile ungulates concluded that research was needed to determine the predisposition of these juveniles to predation. Since then, various characteristics that potentially predispose juvenile ungulates have emerged including blood characteristics, morphometric and other condition factors, and other factors such as birth period, the mother’s experience, and spatial and habitat aspects. To the extent that any of …

Bears Remain Top Summer Predators, Shannon M. Barber, L. David Mech, P. J. White

USGS Northern Prairie Wildlife Research Center

In the ten years since wolves (Canis lupus) were restored to Yellowstone National Park (YNP), elk (Cervus elaphus) numbers have substantially decreased. The northern range elk herd is the largest elk herd in Yellowstone, and constitutes the majority of the park’s elk population. During 1994–2005, early winter counts of northern Yellowstone elk decreased from 19,045 to 9,545. Also, during winters 2000–2004, calf:cow ratios declined from 29:100 to 12:100, and were among the lowest recorded during the past several decades. Though many factors (e.g., predation, hunting, and drought) likely contributed to this decreasing abundance and low recruitment, …

Winter Severity And Wolf Predation On A Formerly Wolf-Free Elk Herd, L. David Mech, Douglas W. Smith, Kerry M. Murphy, Daniel R. Macnulty

USGS Northern Prairie Wildlife Research Center

We studied wolf (Canis lupus) predation on elk (Cervus elaphus) in Yellowstone National Park from 17 March to 15 April 1997 (severe winter conditions) and from 2 to 31 March 1998 (mild winter conditions) 2-3 years after wolves were reintroduced to the park. Elk composed 91% of 117 kills. Data comparisons for 1997 versus 1998 were: hunting success rate, 26% versus 15%; kill rate, 17.1 kg/wolf/day versus 6.1; percent of kill consumed in first day, 7 versus 86; percent femur marrow fat of adult kills, 27 versus 70; calf:adult ratios of kills, 2:33 versus 17:23; sex …

Managing Minnesota's Recovered Wolves, L. David Mech

USGS Northern Prairie Wildlife Research Center

The Minnesota wolf (Canis lupus) population was estimated by the Minnesota Department of Natural Resources at 2,450 during winter 1997-1998 and had increased at an average annual rate of 4.5°% since winter 1988-1989. The population may be removed from the federal endangered species list by 2002, and management would then return to the state. A federal recovery team recommended a population goal of 1,250-1,400 wolves for Minnesota, with none in the agricultural region. A plan approved by the Minnesota legislature, however, continues the protection of wolves, except for pet and livestock depredation control, for at least 5 years …

Do Wolves Affect White-Tailed Buck Harvest In Northeastern Minnesota?, L. David Mech, Michael E. Nelson

USGS Northern Prairie Wildlife Research Center

We used simple linear regression to analyze 8-23 years of data on a wolf (Canis lupus) population and human harvest of white-tailed deer (Odocoileus virginianus) bucks in northeastern Minnesota to determine any effects of wolves on buck harvesting. Over the long term, wolves accounted for at least 14-22% inter-year variation in buck harvest in the region, but an unknown amount of variation in hunter effort have obscured any more precise estimate. For part of the area with poorest habitat, we found strong relationships (r² = 0.66-0.84) between annual wolf numbers and buck harvests from 1988 …

A Record Large Wolf, Canis Lupus, Pack In Minnesota, L. David Mech

USGS Northern Prairie Wildlife Research Center

This report documents a pack of 22-23 Wolves (Canis lupus) in central Minnesota. This is larger than the largest pack previously observed on the mainland in the midwestern U.s. during 650 wolf pack-years. Because this record-large pack preyed on White-tailed Deer (Odocoileus virginianus), one of the Wolfs smaller prey, it is evidence that pack size and prey size are not tightly related. It also indicates the size that Wolf packs can attain in the area if fully protected from human persecution.

The Challenge And Opportunity Of Recovering Wolf Populations, L. David Mech

USGS Northern Prairie Wildlife Research Center

The gray wolf once inhabited a wide variety of habitats throughout most of the northern hemisphere north of 20°N latitude. Because the animal preyed on livestock and competed with humans for wild prey, it was extirpated from much of its range outside of wilderness areas. Environmental awareness in the late 1960s brought for the wolf legal protection, increased research, and favorable media coverage. The species has increased in both Europe and North America, is beginning to reoccupy semiwilderness and agricultural land, and is causing increased damage to livestock. Because of the wolfs high reproductive rate and long dispersal tendencies, the …

Wolf Population Survival In An Area Of High Road Density, L. David Mech

USGS Northern Prairie Wildlife Research Center

Wolf mortality in a high-road-density area of Minnesota exceeds that in an adjacent wilderness, and is primarily human-caused. The wolf population there is maintained primarily by ingress from the adjacent wilderness areas. A road density of 0.58 km/km² can be exceeded and the area still support wolves if it is adjacent to extensive roadless areas.

Mortality Of White-Tailed Deer In Northeastern Minnesota, Michael E. Nelson, L. David Mech

USGS Northern Prairie Wildlife Research Center

Abstract: Two hundred nine white-tailed deer (Odocoileus virginianus) were radiotracked in the central Superior National Forest, Minnesota, from 1973 through winter 1983-84; 85 deaths were recorded. Annual survival was 0.31 for fawns (<1.0 years old), 0.80 for yearling (1.0-2.0 years old) females, 0.41 for yearling males, 0.79 for adult (≥2.0 years old) females, and 0.47 for adult males. Monthly survival rates were high from May through December (0.94-1.00), except for yearling (0.60) and adult (0.69) bucks during the November hunting season. Most mortality occurred from January through April when gray wolf (Canis lupus) predation was an important mortality source for all cohorts. Yearlings males were most vulnerable to hunting and adult males to wolf predation.

Relationship Between Snow Depth And Gray Wolf Predation On White-Tailed Deer, Michael E. Nelson, L. David Mech

USGS Northern Prairie Wildlife Research Center

Abstract: Survival of 203 yearling and adult white-tailed deer (Odocoileus virginianus) was monitored for 23,441 deer days from January through April 1975-85 in northeastern Minnesota. Gray wolf (Canis lupus)predation was the primary mortality cause, and from year to year during this period, the mean predation rate ranged from 0.00 to 0.29. The sum of weekly snow depths/month explained 51% of the variation in annual wolf predation rate, with the highest predation during the deepest snow.

Population Regulation In Wolves, Jane M. Packard, L. David Mech

USGS Northern Prairie Wildlife Research Center

The possibility of social regulation of wolf populations has been discussed in the literature for several years. Some of the first ecological studies of wolves indicated that their populations did not increase as rapidly as was theoretically possible, and that they reached a saturation point apparently not set by food. Subsequent captive studies demonstrated the existence of social mechanisms possibly capable of regulating population growth. However, the importance of these factors in wild populations has not been established. This paper has four objectives: (1) to evaluate the existing concept of "intrinsic limitation," (2) to propose that wolf population dynamics may …

Relating Wolf Scat Content To Prey Consumed, Theodore J. Floyd, L. David Mech, Peter A. Jordan

USGS Northern Prairie Wildlife Research Center

In 9 trials, captive wolves (Canis lupus) were fed prey varying in size from snowshoe (Lepus americanus) to adult deer (Odocoileus virginianus), and the resulting scats were counted. collectible scats were distinguished from liquid, noncollectible stools. In collectible scats, the small prey occurred in greater proportion relative to the prey's weight, and in lesser proportion to the prey's numbers, than did the remains of larger prey. A regression equation with an excellent the data (r² = 0.97) was derived to estimate the weight of prey eaten per collectible scat for With this information …

Canis Lupus., L. David Mech

USGS Northern Prairie Wildlife Research Center

Order Carnivora, Family Canidae. The genus Canis includes eight species. Approxi- mately 24 New World and eight Old World subspecies of C. lupus are recognized, the number depending on authorities accepted. For summary, see Mech (1970); for full synonymy, see Pocock (1935), Goldman (1944), Ellerman and Morrison- Scott (1951), Novikov (1956), and Hall and Kelson (1959).