Showing papers in "Northeastern Naturalist in 2002"
TL;DR: In this paper, an impact source determination method, used to identify point and non-point sources of impacts to stream water quality on the basis of benthic macroinvertebrates, was examined for concordance with impairment sources inferred from chemical and physical site characteristics.
Abstract: An Impact Source Determination method, used to identify point and nonpoint sources of impacts to stream water quality on the basis of benthic macroinvertebrates, was examined for concordance with impairment sources inferred from chemical and physical site characteristics, watershed characteris- tics, and biomonitoring results collected from 26 sites in the Hudson River Basin during 1993-94. Most classifications agreed with the resulting interpreta- tions; site locations on Canonical Correspondence Analysis triplots corre- sponded with interpretation of environmental gradients as (1) overall pollution including organic enrichment and contaminants from point and nonpoint sources, (2) nonpoint nutrients from both agricultural and urban sources, and (3) sediment and suspended organic carbon from agricultural runoff. High-level taxonomic resolution was important in identifying the environmental gradients, and may be necessary for impairment source identification.
48 citations
TL;DR: 46 phytoplankton species that are potentially toxic to humans, or harmful to marine life, or both are described in the area of interest, which is southeastern Nova Scotia to the Hudson River estuary.
Abstract: We have described the occurrence of 46 phytoplankton species that are potentially toxic to humans, or harmful to marine life, or both. The area of interest is southeastern Nova Scotia to the Hudson River (NY) estuary. The species are distributed across a number of taxonomic classes, and represent a conservative estimate of the real total, which must remain speculative until the biodiversity of phytoplankton in the area is known. Despite the high number of potential harmful algal bloom (HAB) species, rather few are known to cause problems.
46 citations
TL;DR: Experimental field studies at two sites in Long Island Sound have demonstrated that the nonindigenous Asian shore crab, Hemigrapsus sanguineus deHaan 1853, is a highly mobile grapsid crab that shows limited fidelity to a particular shelter or feeding site.
Abstract: Experimental field studies at two sites in Long Island Sound have demonstrated that the nonindigenous Asian shore crab, Hemigrapsus sanguineus deHaan 1853, is a highly mobile grapsid crab that shows limited fidelity to a particular shelter or feeding site. Recovery rates of tagged crabs differed significantly at the two sites, but no differences in site fidelity were measurable between males and females at either site. Between-site differences in percent crabs recovered may be due to differences in food and shelter availability at the two sites. There is some suggestion that familiarity with a shelter site may influence site fidelity by leading to reduced mobility. A conservative estimate (based on recovered crabs only) of the mean distance traveled in 24 hours (n = 38) was 7.43 ± 1.54 m; among those crabs recovered a distance > 5 m from the release point (n = 15) the mean distance traveled was 16.87 ± 2.23 m. The rapid, widespread dispersal characteristic of the Asian crab invasion along the eas...
40 citations
TL;DR: Differences in lichen presence and abundance in natural and managed coniferous forests of Nova Scotia were studied and multiple linear regression was used to determine the forest structural features that best explained the abundance of each lichen taxon.
Abstract: Differences in lichen presence and abundance in natural and managed coniferous forests of Nova Scotia were studied in thirty stands catego- rized as 1) harvested and thinned, 2) harvested and unthinned, and 3) naturally disturbed. The frequency of cover of thirty-four lichen taxa was assessed and analysed to examine the effects of forest management history. Nine taxa had significantly greater abundance and two taxa only occurred in old growth forests compared to younger stages. Twenty taxa had significantly greater abundance and five taxa only occurred in natural forests compared to managed forests. The abundance and habitat of each taxon is discussed. Multiple linear regression was used to determine the forest structural features that best explained the abun- dance of each lichen taxon. Tree age, remnant trees, crown closure, tree volume, and tree spacing were structural features that most consistently influenced lichen abundance.
30 citations
TL;DR: Support is found for the hypothesis that the presence of N. defodiens on a carcass provides clues to searching N. orbicollis and for the suggested presence of efficient carrion searchers such as N.defodiens that may significantly increase the numbers and success of the Nicrophorus guild.
Abstract: The larger-bodied burying beetle, Nicrophorus orbicollis, com- petes with the smaller N. defodiens for valued, protein-rich, carrion resources. We tested four hypotheses of this competitive relationship. We found support for the hypotheses that N. defodiens locates fresh carcasses more quickly than N. orbicollis and that carcasses placed under the leaf litter are more difficult for Nicrophorus to locate than carcasses placed above the leaf litter. By shifting the photocycle of N. defodiens we were able to manipulate this normally crepuscular species into beginning its active period 3 h later, during the active period of the nocturnal N. orbicollis. This clock-shift eliminates the 3 h head start that N. defodiens typically experiences in the field. We did not find support for the hypothesis that clock-shifted N. defodiens would suffer in competition compared to non-clock-shifted beetles. We did find support for the hypothesis that the presence of N. defodiens on a carcass provides clues to searching N. orbicollis. We suggest that the presence of efficient carrion searchers such as N. defodiens may significantly increase the numbers and success of the Nicrophorus guild.
28 citations
TL;DR: The location of Nauset Marsh and other estuaries on Cape Cod provide a unique opportunity to evaluate the importance of this region as a faunal boundary to estuarine species.
Abstract: Sampling in several habitat types (sand/mud, eelgrass, sand, gravel, macroalgae/mud) during all seasons with a variety of gears in Nauset Marsh, Massachusetts during 1985–1987 found a fauna consisting of 35 fish and 10 decapod crustacean species. Although most of the abundant species were found in several habitat types, species richness and habitat use appeared to be highest for vegetated habitats (eelgrass, macroalgae). The fishes and decapods were numerically dominated by cold-water taxa; however, numerous fish species, represented by rare individuals of predominantly southern forms, enriched the fauna. Species composition of Nauset Marsh could be distinguished from estuaries south of Cape Cod and even from the south shore of the cape. Both fishes and decapods were most abundant during the summer, apparently due to the contributions from spring and summer spawning in the estuary and the adjacent Atlantic Ocean. The location of Nauset Marsh and other estuaries on Cape Cod provide a unique opport...
28 citations
TL;DR: A brief review of the taxonomic history and integrity of selected North American branchiobdellidans is given to clarify their current status and distributional anomalies of certain taxa are discussed.
Abstract: A brief review of the taxonomic history and integrity of selected North American branchiobdellidans is given to clarify their current status. The zoogeographical distribution of branchiobdellidans on the North American continent is presented based on published reports and information in the Catalog of the National Museum of Natural History, Smithsonian Institution, Washington, DC. These data are tabulated by species with locations referenced to zoogeographical subregions, political units of provinces, states, or countries, and source citations. Distributional anomalies of certain taxa are discussed.
28 citations
TL;DR: Ant species richness was highest in bogs of the Connecticut River Valley and the Massachusetts-Rhode Island border, areas identified by the Massachusetts BioMap project as core areas for biodiversity in the state.
Abstract: We conducted the first systematic inventory of ant species richness in pitcher-plant bogs of Massachusetts. Twenty-six species were collected in 18 bogs during 1999 and 2000. We collected the bog-specialist Myrmica lobifrons for the first time in Massachusetts and found that it occurred in bogs from the Berkshire Mountains to Nantucket. Ant species composition in bogs displayed a nested subsets pattern, in which the species composition of a bog with few species was generally a subset of the species composition of bogs with more species. This pattern appears to result from different colonization histories of the different bogs. We tested whether ant species richness differed among bog types, ecological subregions, or geographic regions of the state (mainland, Cape Cod, Islands), and whether ant species richness was correlated with variables measured at each bog including: latitude, longitude, elevation, bog mat area; vegetation composition and the density of the carnivorous plant Sarracenia purpurea; and nutrient availability. Among Massachusetts bogs, species richness of ants was predicted best by tree species richness within bogs and by the concentration of ammonium in bog pore-water. Ant species richness was highest in bogs of the Connecticut River Valley and the Massachusetts-Rhode Island border. These are also areas identified by the Massachusetts BioMap project as core areas for biodiversity in the state.
23 citations
TL;DR: The marine waters of New York State (excluding the Hudson River) are home to a large and diverse ichthyofauna that includes pelagics, migratory coastal fishes, resident species, anadromous and cat adromous fishes, euryhaline-estuarine forms, and freshwater and deep-ocean strays.
Abstract: The marine waters of New York State (excluding the Hudson River) are home to a large and diverse ichthyofauna that includes pelagics, migratory coastal fishes, resident species, anadromous and catadromous fishes, euryhaline- estuarine forms, and freshwater and deep-ocean strays. This diversity is attributable, in part, to the broad variety of habitats composing New York's marine waters. Also, although New York is located near the center of the Virginian biogeographic prov- ince, seasonal representatives of the Acadian and Carolinian provinces increase the breadth of its ichthyofauna. We record 338 fishes (114 families) reported from these waters, with annotations where warranted. Rare and unusual specimens are docu- mented where possible with museum and literature citations.
20 citations
TL;DR: The diet of young-of-the-year white perch in the Richibucto Estuary was found to be similar to that of young of the year striped bass studied previously in the Miramichi Estuary.
Abstract: The Richibucto Estuary, located in the southern Gulf of St. Lawrence, is rearing habitat for a population of white perch (Morone americana), as well as for young-of-the-year striped bass (M. saxatilis) which immigrate from the nearby Miramichi Estuary. In this study we compared the diet of white perch caught in the Richibucto Estuary to a previously published account of the diet of young-of-the-year striped bass in the Miramichi Estuary. One hundred and fifteen white perch of 26–168 mm total length (TL) were collected from the Richibucto Estuary between 25 June and 10 October 1998 by onshore beach seining at 10 sites. Eighty-nine percent of their stomachs contained food. Sand shrimp (Crangon septemspinosa) were found in 69–79% of stomachs and constituted at least 80% of total dietary weight for white perch = 50 mm TL. Copepods (cyclopoids and the large calanoid Eurytemora sp.) constituted almost all of the diet of small white perch (<50 mm TL) found in low salinity but in higher salinities (11–20...
17 citations
TL;DR: Wheeler Marsh in Milford, Connecticut provides habitat for diamondback terrapins (Malaclemys terrapin), a unique estuarine turtle, and the physical structure, plant density, and tidal amplitudes of salt marsh creeks may also be important determinants of terRapin distribution via their influence on resource accessibility.
Abstract: Wheeler Marsh in Milford, Connecticut provides habitat for diamondback terrapins (Malaclemys terrapin), a unique estuarine turtle. To assess potential prey availability, the distribution and abundances of marsh snails (Melampus bidentatus), mud snails (Ilyanassa obsoleta), marsh mussels (Geukensia demissa), and fiddler crabs (Uca spp.) were studied in several sub-habitats (marsh surface, marsh edge, creek bank, and mudflats) of five tidal creeks. Almost all terrapins have been found in one section of the marsh, Turtle Creek, where all four prey species were present in large numbers. However, high numbers of some prey were found in other sections of the marsh as well, suggesting that resource availability may not be the primary determinant of terrapin distribution. The physical structure, plant density, and tidal amplitudes of salt marsh creeks may also be important determinants of terrapin distribution via their influence on resource accessibility.
TL;DR: The most frequently detected species were Soras, Pied-billed Grebes, and Vir- ginia Rails as mentioned in this paper, and they recommend using call broadcast surveys for these cryptic species to enhance their probabilities of detection.
Abstract: We initiated an inventory and a field test of a protocol that could be used for monitoring marsh birds at the Cape Cod National Seashore in eastern Massachusetts during 1999 and 2000, as part of a more comprehensive national effort. Using cassette tapes during call broadcast surveys, we visited a total of 78 survey points at freshwater, brackish, and salt marsh sites three times on the ground or in canoes during the breeding season (May-June), fall migra- tion (September to November), and twice during winter (December-January). Observer bias on our marsh bird surveys appeared negligible. Although both auditory and visual detection of most species was low (mean < 0.3 birds per replicate-survey point), we confirmed the presence of seven marsh species, including American Bittern (Botaurus lentiginosus), Least Bittern (Ixobrychus exilis), American Coot (Fulica americana), King Rail (Rallus elegans), Pied- billed Grebe (Podilymbus podiceps), Sora (Porzana carolina), and Virginia Rail (Rallus limicola). We suspected breeding of Least Bitterns and Soras at Great Pond in Provincetown, and for Virginia Rails at Hatches Harbor, Provincetown. The most frequently detected species were Soras, Pied-billed Grebes, and Vir- ginia Rails. We recommend using call broadcast surveys for these cryptic species to enhance their probabilities of detection.
TL;DR: In this article, the authors examined the correlation between canopy gap formation and the initial growth of forest trees by reconstructing the gap history of a Tsuga canadensis (L.) Carr community in southeastern Ohio.
Abstract: We examined the correlation between canopy gap formation and the initial growth of forest trees by reconstructing the gap history of a Tsuga canadensis (L.) Carr. forest community in southeastern Ohio. We cored each tree (>10 cm dbh, n = 156) in a 40 × 90 m plot and examined the cores for release events, characterized by dramatic increases in radial growth. We identified 80 former gaps in the 79 yr sample period by clustering release events in time and space. Thirteen of the 80 former gaps coincided with the initial growth of trees. These 13 gaps were usually large gaps containing few established trees or gaps undergoing repeat disturbance. Of the 36 trees >10 cm dbh that began growth during the sample, 21 (58%) began growing inside a gap within 6 yr of gap formation-three times the rate predicted by chance (p = 0.001). We also measured the distance in time and space between the first year of growth and the closest canopy gap for each tree. We called the inverse of this measure the gap affinity i...
TL;DR: Harp seals are sighted in substantial numbers in both the southern and northern Gulf of Maine, and the reason for this general increase, as well as the reasons for the spike in 2001, are unknown.
Abstract: Harp seals (Phoca groenlandica) whelp on the North Atlantic pack ice in early spring, move north in the summer and then, historically, return as far south as Nova Scotia in the fall. Because recent reports document increased sightings in the northern Gulf of Maine, we reviewed records of harp seal sightings between Kittery and Rockland, Maine to determine if this increase is also occurring in the southern Gulf. From 1997 to 2001 we found 357 confirmed reports of harp seal sightings. Most (85%) occurred in the first quarter of the year and almost all (96%) were juveniles. The total sightings for 2001 (N=238) greatly exceeded the number in any other year. The weight and health status of the seals sighted in 2001 was no different from those of previous study years. Thus, harp seals are sighted in substantial numbers in both the southern and northern Gulf of Maine. The reason for this general increase, as well as the reason for the spike in 2001, is unknown.
TL;DR: Between 1,150 to 1,300 Harlequin Ducks wintered in Maine in the late 1990s, which represents over 50% of the total known wintering population in eastern North America and should remain under full protection in the foreseeable future.
Abstract: We estimate between 1,150 to 1,300 Harlequin Ducks wintered in Maine in the late 1990s. This represents over 50% of the total known wintering population in eastern North America. About 75% of these wintering birds in Maine were located in the Isle au Haut area from Vinalhaven to Swans Island. Smaller concentrations of birds were also present in eastern Hancock County (Sally Islands area) and York County (Cape Neddick area). At four groups of islands in the Isle au Haut area, numbers show a pattern of decline from 1989 to 1993 followed by increases since then. In contrast, the maximum number of birds reported each winter in York County has increased from about five birds in 1955 to about 75 birds in 1999 (rs = 0.73, n = 42, P < 0.001). The proportion of males to females observed during mid-winter counts increased from a low of 0.8:1.0 in 1992 to a high of 1.2:1.0 in 1996 (rs = 0.54, n = 35, P = 0.001) and averaged 1.0:1.0 (n = 35, SD = 3.5) from 1989–99. Given the small numbers and limited distrib...
TL;DR: Analysis of larval microhabitat variables identified sand texture as the most important determinant of habitat suitability, and recommends reintroducing C. puritana to an area in the vicinity of Windsor, CT where there are beaches on three islands that appear to be suitable larval habitat.
Abstract: For Cicindela puritana to be a viable member of New England's biota, there must be more than the current two occurrences. Assessment of the chance that the species can spread, whether on its own or through reintroduc- tion, required identifying vacant habitat patches, which in turn, required refining the description of the species' larval habitat. Analysis of larval microhabitat variables identified sand texture as the most important determinant of habitat suitability. I then surveyed a 79 km stretch of the Connecticut River in Connecti- cut looking for suitable habitat patches. Of 32 beaches, none that appeared to be suitable was nearer than 12 km from currently occupied patches. Dispersal is unlikely to lead to establishment of new populations, so I recommend reintro- ducing C. puritana to an area in the vicinity of Windsor, CT where there are beaches on three islands that appear to be suitable larval habitat.
TL;DR: The epiphytic moss and organic soil horizon are selected for use in future studies as biomonitors to evaluate spatial and temporal variations of Hg within the mixed-hardwood forests of Pennsylvania.
Abstract: Total mercury (Hg) content was determined in an epiphytic moss (Dicranum montanum Hedw.); a corticolous macrolichen (Punctelia subrudecta (Nyl.) Krog) growing on tree bark; tree foliage from black cherry (Prunus serotina Ehrh.), red maple (Acer rubrum L.) and northern red oak (Quercus rubra L.); red oak leaf litter (freshly fallen leaves); the organic soil horizon; and mineral soil within an oak forest in southwestern Pennsylvania during 1999. Mean Hg concentrations of tree leaves and red oak litter were low (averaging 0.05 to 0.10 µg/g). The mineral soil contained slightly higher Hg contents (0.12 µg/g). Total Hg concentrations in the lichen species, organic soil horizon, and the epiphytic moss averaged 0.18, 0.43 and 0.50 µg/g, respectively. Based on these results, we selected the epiphytic moss and organic soil horizon for use in future studies as biomonitors to evaluate spatial and temporal variations of Hg within the mixed-hardwood forests of Pennsylvania.
TL;DR: It is demonstrated that the secretion of this introduced beetle serves as a potent antipredator defense: contact with it elicited pronounced cleaning activity by the predatory ant Crematogaster lineolata, and application of the secretion to palatable food items rendered them unacceptable to the ant.
Abstract: Subcoccinella vigintiquatuorpunctata, an herbivorous coccinellid beetle of Eurasian origin, is now established in New England, as evidenced by the persistence of two central Connecticut populations from 1997–2001. The beetle's pupal surface bears glandular hairs that produce a secretion known to consist principally of three polyazamacrolide alkaloids. We demonstrate that the secretion serves as a potent antipredator defense: contact with it elicited pronounced cleaning activity by the predatory ant Crematogaster lineolata. Additionally, application of the secretion to palatable food items rendered them unacceptable to the ant. This is one of few studies to examine the chemical defense of an introduced animal vis a vis a predator native to its new environment.
TL;DR: Two kleptoparasitic scorpionflies were observed stealing food from Araneus bicentenarius (McCook) (Araneae: Araneidae) at Waterboro Barrens Preserve, York County, Maine, which is the first recorded instance of kleptonitism by scorpionfly on an orb-weaving spider in Maine.
Abstract: Two kleptoparasitic scorpionflies, Panorpa rufescens Rambur (Mecoptera: Panorpidae), were observed stealing food from Araneus bicentenarius (McCook) (Araneae: Araneidae) at Waterboro Barrens Preserve, York County, Maine. The spider's ensnared prey was a larva of Lapara sp. (Lepidoptera: Sphingidae), which provided food for both spider and kleptoparasites. This is the first recorded instance of kleptoparasitism by scorpionflies on an orb-weaving spider in Maine.
TL;DR: Nitrogen and phosphorus were measured in large and small fully senesced leaves of Acer rubrum and Quercus alba to determine whether leaf size influences nutrient resorption proficiency, and leaf size did not play a role in controlling nitrogen or phosphorus resOrption proficiency in these two deciduous forest species.
Abstract: Nitrogen and phosphorus were measured in large and small fully senesced leaves of Acer rubrum and Quercus alba to determine whether leaf size influences nutrient resorption proficiency. Large Acer leaves were ≥ 3.3 times higher in mass and surface area than small Acer leaves collected from the same individual trees, yet concentrations of nitrogen and phosphorus in large and small senesced leaves (i.e., resorption proficiency of these two nutrients) were identical. Large Quercus leaves were ≥ 2.8 times higher in mass and surface area than small Quercus leaves collected from the same individual trees, yet concentrations of nitrogen and phosphorus were nearly identical in large and small senesced leaves. Although there are theoretical reasons to expect leaf size to influence resorption, leaf size did not play a role in controlling nitrogen or phosphorus resorption proficiency in these two deciduous forest species.
TL;DR: Propagules of four species of the algal genus Vaucheria are shown to survive enteric passage through the exotic earthworm, Metaphire levis, and it is postulate that they can also be the source of dispersal of Vauchersia propagules which, when wafted into the atmosphere as dust from castings, could disperse to nearby or distant locations.
Abstract: Propagules of four species of the algal genus Vaucheria—V. aversa, V. frigida, V. prona, and V. undulata—are shown to survive enteric passage through the exotic earthworm, Metaphire levis. One species previously known from the northeastern Connecticut collection site, V. geminata, did not appear in the worm castings cultures, and another, V. aversa, was previously unknown there. In that earthworm castings are a mechanism for the movement of soils, we postulate that they can also be the source of dispersal of Vaucheria propagules which, when wafted into the atmosphere as dust from castings, could disperse to nearby or distant locations.
TL;DR: In this article, the authors employed the comet assay to measure the level of genotoxicity induced in a sentinel animal species, Micropterus dolomieu, in the Androscoggin River.
Abstract: In order to better illuminate the genotoxic effects of a “complex mixture” of anthropogenic chemical toxins, we have employed the comet assay to measure the level of genotoxicity induced in a sentinel animal species, Micropterus dolomieu. Our analysis reveals a significant level of genetic damage in Androscoggin River smallmouth bass that increases in a downstream gradient in parallel with toxic equivalent concentrations. Individual concentrations of recognized, anthropogenic chemical toxins in Androscoggin River fish tissues are measured on an annual basis as part of a State monitoring program. Subsequent fish consumption and river use advisories are issued based, in part, on these assessments.
TL;DR: At both parks, an effort should be made to develop mowed lawns into unmowed grasslands to increase their use by butterfly species by providing habitat for wildflowers (nectar sources).
Abstract: Butterfly communities were inventoried at two national parks, Allegheny Portage Railroad National Historic Site (ALPO) and Johnstown Flood National Memorial (JOFL), Pennsylvania, in 1998. Information on presence, abundance, and distribution of butterflies is important to National Park Service personnel, who are mandated to manage the biodiversity of natural resources. As large tracts of public lands, such as national parks, become more insular with increased habitat fragmentation, they will become increasingly valuable for the long-term maintenance of faunal diversity and the functional integrity of ecosystems in the eastern United States. Surveys were conducted monthly from late spring to early fall along two transects in ALPO and one in JOFL. Twenty-eight butterfly species were noted in the study. At ALPO, most species and individuals were found along open (non-wooded) sectors of the transects, including Phyciodes tharos (Drury) (Pearl Crescent), Boloria bellona (F.) (Meadow Fritillary), and Thymelicus lineola (Ochs.) (European Skipper). At JOFL, the most abundant butterfly was T. lineola. We observed 27 of 110 flowering plant species being used as nectar sources by butterflies on 200 occasions in both parks combined. At both parks, an effort should be made to develop mowed lawns into unmowed grasslands to increase their use by butterfly species by providing habitat for wildflowers (nectar sources).
TL;DR: The specimen (AMNH-R 144501) could be the only known partial albino specimen of the species and is one of only a few such snakes known from localities in the northeastern United States.
Abstract: A partial albino Storeria occipitomaculata occipitomaculata (Storer 1839) was field-collected in Vermont on 25 July 1998. The specimen (AMNH-R 144501) could be the only known partial albino specimen of the species and is one of only a few such snakes known from localities in the northeastern United States. The existence of color variations in wild snake populations is discussed.
TL;DR: Many of Vermont's turtles were determined to be significantly different from typical marginata and picta, and were intermediate to them, strongly suggesting that they are intergrades.
Abstract: The painted turtle, Chrysemys picta Schneider (family Emydidae), has been divided into four subspecies (with differing morphological characteristics), two of which intergrade in the northeastern United States. The intergradation of C. p. marginata (midland painted turtle) and C. p. picta (eastern painted turtle) has been well studied in some areas, but has been poorly studied in Vermont, an area that could contribute important information on this species and the process of intergradation. Turtles were trapped and released from three different watersheds in Vermont, and others were examined from collections at the Carnegie Museum of Natural History from within the center of the ranges of the two parent subspecies to investigate the hypotheses that Vermont's turtles are intergrades, and that the amount of influence from each subspecies differs with drainage in Vermont. For the external characteristics of scute disalignment, scute border width, and plastral figure, many of Vermont's turtles were det...
TL;DR: The nesting behavior of >300 females of Oxybelus bipunctatus was studied for 15 straight weeks in a sandpit in central New York during late spring-summer 1985 and the number of prey per cell was rather uniform throughout the nesting season despite much variation in the prey fly families.
Abstract: The nesting behavior of >300 females of Oxybelus bipunctatus was studied for 15 straight weeks in a sandpit in central New York during late spring-summer 1985. Cool and rainy weather in late spring induced moldy conditions in the cells that caused much larval mortality. Successive generations of wasps emerged in the field and laboratory every four to six weeks. Cells were always excavated in moderately damp sand. Cell depth varied inversely with soil moisture as tied to the amount of rainfall. Female cocoons were larger and heavier than male cocoons, but they did not occupy deeper or shallower cells. One-celled nests were predominant in this species. The number of prey per cell was rather uniform throughout the nesting season despite much variation in the prey fly families. Individual and aggregate prey weight per cell decreased slightly through the summer. Male Cyclorrapha were preyed upon more than any other taxon.
TL;DR: In 2000 and 2001, the only known North American breeding colony of Manx Shearwater (Puffinus puffinus) on Middle Lawn Island, Newfoundland was visited as discussed by the authors.
Abstract: In 2000 and 2001, the only known North American breeding colony of Manx Shearwater (Puffinus puffinus) on Middle Lawn Island, Newfoundland was visited. Breeding was first confirmed in 1977 and by 1981, a minimum of 13 pairs laid eggs. In 2000, a complete assessment of all burrows was undertaken, and only 2 eggs were found; a third female had an egg in her oviduct. Based on female call rates, capture of birds, and offshore observations, the numbers of non-breeding shearwaters around Middle Lawn Island was comparable to the early 1980s, in the low 100s. The growth of a nearby large gull colony, changing marine ecosystems, and a short breeding season in the northwest Atlantic are possible explanations for why this colony has not become better established. Similar conditions could also be keeping the small Northern Fulmar (Fulmaris glacialis) and Common Black-headed Gull (Larus ridibundus) breeding populations in Atlantic Canada from expanding.
TL;DR: In this article, the authors documented successful breeding by a pair of Sandhill Cranes (Grus canadensis) in a wetland in Kennebec County, Maine in 2000 and 2001.
Abstract: I documented successful breeding by a pair of Sandhill Cranes (Grus canadensis) in a wetland in Kennebec County, Maine in 2000 and 2001. In 2000 I observed two adults with a chick on 5 and 14 July and 5 August. In 2001 I found the pair incubating a nest with two eggs on 18 May and observed them with one chick on 3 and 22 July. The wetland is a large sedge- and sphagnum-dominated lakeside fen and cattail (Typha latifolia) marsh that supports one of the most diverse wetland bird communities in the state. The nest was surrounded by cattails and was constructed of year-old cattail leaves and stems. These first records of breeding Sandhill Cranes in Maine and New England are likely the result of recent increases and eastward expansion of a crane population centered in the midwestern United States and Ontario. Historical literature suggests that this species was formerly a common migrant north to New England and may have nested here as well.
TL;DR: In this article, the authors examined 27 wetlands and analyzed water quality and depth data, the composition of aquatic invertebrate assemblages, and land use patterns, concluding that both hydrologic cycle and upland development are important in limiting the local distribution of Williamsonia lintneri.
Abstract: Williamsonia lintneri is a rare dragonfly species restricted to southern New England and some northern states. In 1999, I tested the hypothesis that upland development around wetlands reduces habitat suitability for W. lintneri through increased nutrient runoff. I examined 27 wetlands and analyzed water quality and depth data, the composition of aquatic invertebrate assemblages, and land use patterns. Sites where W. lintneri was present did not differ in water quality from sites where it was absent (i.e., null sites). However, W. lintneri sites had significantly deeper levels of water throughout the summer, were dry for shorter periods of time, and had significantly lower levels of development in the surrounding uplands than did null sites. These results suggest that both hydrologic cycle and upland development are important in limiting the local distribution of this species.
TL;DR: The 2 males were together most frequently during the pup-rearing and dispersal seasons, suggesting provisioning of pups and vigilance at diurnal resting sites as possible mechanisms for the dyad formation.
Abstract: As part of a larger study, we investigated the intensity and duration of association between 2 adult male coyotes (Canis latrans) in an agrarian landscape in west-central Indiana. Home-range size and overlap and the intensity of association varied with time. Home-range sizes averaged 7.9 ± 1.1 (SE) and 11.8 ± 0.9 km2, and spatial overlap was substantial. Activity patterns and habitat preferences were similar for the coyotes whether together or apart, and there was no evidence of temporal or spatial avoidance. The 2 males were together most frequently during the pup-rearing and dispersal seasons, suggesting provisioning of pups and vigilance at diurnal resting sites as possible mechanisms for the dyad formation.