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E.M. Kirsch

Publications and source records attributed to E.M. Kirsch.

12 recordsLinked to original sources
USGS2008

Assessing habitat use by breeding Great Blue Herons (Ardea herodias) on the Upper Mississippi River, USA

Approximately 7,610 to 3,175 pairs of Great Blue Herons ( Ardea herodias ) nested along 420 river km of the Upper Mississippi River (UMR) from 1993 to 2003. Numbers declined precipitously in the mid-1990s stabilizing somewhat in the early 2000s. The average number of nests in colonies was 349 (SD = 283). Annual colony turn over rate for the eleven year period was 0.15 and ranged from 0.06 to 0.29 each year. The number of years that a colony was active was positively correlated with the average number of nests present while the colony was active. Of the eight colonies active in 1993 that averaged more than 349 nests, four were abandoned by 2003. Only one colony grew to greater than 349 nests during the study period. Custer et al. (2004) suggested that herons on the UMR may be limited by forage resources or foraging habitat and social factors, as evidenced by the even spacing of colonies that reflects the maximum feeding range of herons on the river. To rule out nesting and foraging habitat limitation, landscape habitat features of terrestrial and aquatic areas were examined for colony areas and areas without colonies. Available fish monitoring data were used to examine potential interactions between herons and forage resources. Colony areas did not differ from areas without colonies in any habitat feature. Indices of potential heron forage fish increased from 1993 to 2002, although low indices of fish abundance in 1993 were likely influenced by flood conditions that year. Although fish availability to herons is related to flows and water levels, available data suggested that herons did not negatively impact their potential forage base. Numbers of herons were not correlated with indices of fish abundance from the preceding year on a pool-wide scale. Indices of fish abundance were higher within 5 km of colonies than farther than 5 km from colonies, and indices of fish abundance increased from June through August both near and far from colonies. Numbers of herons and locations and sizes of colonies varied annually, whereas landscape features typically vary little if at all from year to year. Indices of fish abundance also varied greatly by sample location and year. Disturbance, particularly by humans in this highly used river, should be examined in relation to limiting foraging opportunities and influencing behavior (colony and individual) and productivity in colonies.

Illinois, Iowa, Minnesota, Missouri, Wisconsin↗
USGS2007

Breeding bird territory placement in riparian wet meadows in relation to invasive reed canary grass, Phalaris arundinacea

Invasive plants are a growing concern worldwide for conservation of native habitats. In endangered wet meadow habitat in the Upper Midwestern United States, reed canary grass ( Phalaris arundinacea ) is a recognized problem and its prevalence is more widespread than the better-known invasive wetland plant purple loosestrife ( Lythrum salicaria ). Although resource managers are concerned about the effect of reed canary grass on birds, this is the first study to report how common wet meadow birds use habitat in relation to reed canary grass cover and dominance. We examined three response variables: territory placement, size of territories, and numbers of territories per plot in relation to cover of reed canary grass. Territory locations for Sedge Wren ( Cistothorus platensis ) and Song Sparrow ( Melospiza melodid ) were positively associated with reed canary grass cover, while those for Common Yellowthroat ( Geothlypis trichas ) were not. Only Swamp Sparrow ( M. georgiana ) territory locations were negatively associated with reed canary grass cover and dominance (which indicated a tendency to place territories where there was no reed canary grass or where many plant species occurred with reed canary grass). Swamp Sparrow territories were positively associated with vegetation height density and litter depth. Common Yellowthroat territories were positively associated with vegetation height density and shrub cover. Song Sparrow territories were negatively associated with litter depth. Reed canary grass cover within territories was not associated with territory size for any of these four bird species. Territory density per plot was not associated with average reed canary grass cover of plots for all four species. Sedge Wrens and Song Sparrows may not respond negatively to reed canary grass because this grass is native to wet meadows of North America, and in the study area it merely replaces other tall lush plants. Avoidance of reed canary grass by Swamp Sparrows may be mediated through their preference for wet areas where reed canary grass typically does not dominate.

Wetlands↗
USGS1997

Small mammal community composition in cornfields, roadside ditches, and prairies in eastern Nebraska

Community composition of small mammals was examined in prairies, cornfields, and their adjacent roadside ditches in eastern Nebraska. Western harvest mice (Reithrodontomys megalotis) and meadow voles (Microtus pennsylvanicus) were associated with prairie habitat, were common in ditches, but avoided cornfields. Prairie voles (M. Ochrogaster) and white-footed mice (Peromyscus leucopus) were associated with ditch habitat, were common in prairies, but avoided cornfields. Short-tailed shrews (Blarina brevicauda) avoided cornfields, were associated with ditches next to cornfields, but were common in prairies and ditches next to prairies. Deer mice (P. Maniculatus) were associated with cornfields but were relatively common in prairies and ditches. House mice (Mus musculus) were most common in ditches next to cornfields, occurred in cornfields and ditches next to prairies, but were not captured in prairies. Although community composition appears to differ among prairies, ditches, and cornfields, ditches support a more complete suite of the native small mammal species in large and relatively even numbers, whereas cornfields only support deer mice in large numbers.

Nebraska↗
USGS1997

Numbers and distribution of Double-crested Cormorants on the upper Mississippi river

Historic records indicate that Double-crested Cormorants (Phalacrocorax auritus) were common breeders and abundant during migration on the Upper Mississippi River from St. Paul, Minnesota, to St. Louis, Missouri, during the 1940s and 1950s. Their numbers declined in the mid- to late-1950s, remained low through the 1970s, and began to increase somewhat in the late 1980s. Aerial surveys of migrating cormorants and ground surveys at cormorant colonies during 1991-1993, indicate that numbers have not returned to historic levels. Only 500-2,000 cormorants were seen during spring migration 1992-1993; and 5,000-7,000 during fall migration 1991-1992; whereas, tens of thousands were reported in the 1940s and 1950s. Four hundred ninety-six nests were counted at 4 colonies in 1992, and 545 nests were counted in 9 colonies in 1993; whereas, during the 1940s and 1950s, about 2,500 birds were reported nesting in 4 locations. Pools 6 and 13 have always attracted breeding and migrating cormorants, currently attract the largest numbers of cormorants during migration, and still support breeding colonies.

Waterbirds↗
USGS1997

Least tern (Sterna antillarum)

This species account discusses: distinguishing characteristics, distribution, systematics, migration, habitat, food habits, vocalizations, behavior (locomotion, maintenance, agonistic, sexual, social, interspecific), breeding (phenology, nest site, nest, eggs, incubation, development of the young, parental care), demography and populations (life span, mortality, dispersal and philopatry, population status), conservation and management, plumages and molt, and measurements. There is also a bibliography which lists key references for additional information. (DBO)

Book↗
USGS1995

Double-crested cormorants along the Upper Mississippi River

The Upper Mississippi River is an important habitat corridor for migratory birds and other wildlife, and it supports an important commercial and sport fishery. A study was initiated by the U.S. Fish and Wildlife Service in 1991 to describe Double-crested cormorant (Phalacrocorax auritus) distribution and abundance on the Upper Mississippi River throughout the year to better understand the possible impacts of cormorants on fish resources and populations of other piscivorous birds. Double-crested Cormorants were common breeders and abundant during migration on the Upper Mississippi River during the 1940s. Numbers of cormorants declined in the 1960s and 1970s along the Upper Mississippi River as they did in other parts of the United States. In 1992, 418 cormorant pairs were estimated to have nested in four colonies on the Upper Mississippi River, and less than 7,000 cormorants were estimated to have migrated along the river during the fall and spring of 1991 and 1992. Recent public concern for fish resources has grown with a perceived growth of the local cormorant population. Migrating cormorants collected on the Upper Mississippi River took Gizzard Shad (Dorosoma cepedianum) primarily, but chicks were fed a wide variety of fish species.

Colonial Waterbirds↗
USGS1993

Least tern and piping plover nesting at sand pits in Nebraska

Endangered Least Terns (Sterna antillarum) and threatened Piping Plovers (Charadrius melodus) nest at commercial sand and gravel mining operations (sand pits) along the Platte River system in Nebraska. Sandbar habitat has been disappearing since the early 1900's along the Platte River system, but numbers of sand pits have increased. We hypothesized that birds would more fully utilize sand pits where suitable sandbar habitat was limited. We inventoried sand pits and censused terns and plovers on both habitats along the Loup River, part of the North Loup River, and most of the Platte River during 1988-1991. Using aircraft, we also quantified features of suitable sand pits present on the central Platte in 1988 and lower Platte in 1990, and related features to abundance and presence of birds. We found 225 sand pits of which 78 were suitable and 187 were unsuitable for nesting. Along the central Platte, where sandbar habitat is severely degraded, birds nested at 81% of the suitable sand pits (N = 32) at least once during 1988-1991, and most birds (61-94%) nested on sand pits. Along the lower Platte, where both sandbar and sand pit habitat are plentiful, birds nested at 60% of the suitable sand pits (N = 35) at least once during 1988-1991, and most birds (60-86%) nested on sandbars. Numbers of terns and plovers were more weakly correlated with features of sand pits on the central Platte than on the lower Platte. Least Terns and Piping Plovers seem to use more of the suitable sand pit habitat on the central Platte than on the lower Platte. Sand pits probably have influenced the birds' distribution by providing alternative nesting habitat along rivers where suitable sandbars are rare or absent.

Nebraska↗
USGS1992

Flooding mortality and habitat renewal for least terns and piping plovers

We observed extensive mortality (eggs and chicks) of the endangered interior population of the Least Tern (Sterna antillarum) and threatened Piping Plover (Charadrius melodus) caused by natural flooding during the 1990 breeding season along the Platte River, Nebraska USA. Aerial videography of the Platte River before and after the flood revealed a 78% reduction of perennial vegetation on sandbars. The flood scoured vegetation from sandbars and greatly increased the amount of barren sandbar habitat that nesting Least Terns and Piping Plovers use. A review of river gauging station data indicated that flooding of the 1990 magnitude or greater can be expected to occur about once every nine years. We recommend a review of the annual operating plans of managed rivers to account for the effects of dam discharges on Least Terns and Piping Plovers.

Colonial Waterbirds↗