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2001

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Articles 151 - 180 of 182

Full-Text Articles in Ecology and Evolutionary Biology

Recommendations For The Attachment Of Satellite Transmitters To Cranes, David H. Ellis, Paul W. Howey, Gary L. Krapu Jan 2001

Recommendations For The Attachment Of Satellite Transmitters To Cranes, David H. Ellis, Paul W. Howey, Gary L. Krapu

Proceedings of the North American Crane Workshop

Recent advances in miniaturization of satellite transmitters have resulted in thumb-sized packages weighing less than 30 g. These are smaller than VHF radios routinely mounted on crane leg bands. With this development and with favorable signal reception results, there is no need for, and much to recommend against, the continued use of back-pack mounts. We provide details for leg-mount attachments.


Resolutions Passed By The North American Crane Working Group Eighth North American Crane Workshop, Albuquerque, New Mexico U.S.A. Jan 2001

Resolutions Passed By The North American Crane Working Group Eighth North American Crane Workshop, Albuquerque, New Mexico U.S.A.

Proceedings of the North American Crane Workshop

Participants of the Eighth North American Crane Workshop hereby express their thanks and appreciation to the Bosque del Apache National Wildlife Refuge for hosting this workshop, to the staff of the Sheraton Old Town Hotel, to the field trip leaders, to the staff of the Bernardo Waterfowl Management Area, and to the committees and individuals who made the workshop a success. The paper sessions were excellent, and the spirit of friendship and dedication to crane conservation among the participants was revitalizing. Special thanks go to NACWG President Scott Hereford and Bosque del Apache Biologist John Taylor for their tireless effort …


Population Genetics Of Midcontinent Sandhill Cranes, Jessica L. Petersen, Richard Bischof, Allen L. Szalanski Jan 2001

Population Genetics Of Midcontinent Sandhill Cranes, Jessica L. Petersen, Richard Bischof, Allen L. Szalanski

Proceedings of the North American Crane Workshop

The Midcontinent Sandhill Crane Population is comprised of 3 subspecies, lesser (Grus canadensis canadensis), Canadian (G. c. rowani), and greater (G. c. tabida) sandhill cranes. In conjunction with the USGS Northern Prairie Wildlife Research Center, we studied the extent of genetic variation between and within each race of the Midcontinent Sandhill Crane Population. DNA was extracted from 150 feather and dried blood samples collected from 1995-99 from sandhill cranes in the Platte River Valley, central Nebraska. Parsimony and maximwn likelihood analysis of the mtDNA D-loop sequences (ca 675 bp amplified using PCR) from 29 …


Aspects Of Reproduction And Pair Bonds In Florida Sandhill Cranes, Stephen A. Nesbitt, Martin J. Folk, Stephen T. Schwikert, James A. Schmidt Jan 2001

Aspects Of Reproduction And Pair Bonds In Florida Sandhill Cranes, Stephen A. Nesbitt, Martin J. Folk, Stephen T. Schwikert, James A. Schmidt

Proceedings of the North American Crane Workshop

From 1980-98 we captured and uniquely marked more than 400 Florida sandhill cranes (Grus canadensis prafensis). Age ratios of the marked population, excluding juveniles, was 66% adult and 33% subadult, and the sex ratio was 49% male and 51% female. Average clutch size for 210 nests checked from 1983-97 was 1.78 ± 0.18 (SD) and frequency of l-egg clutches varied among years. Average post-fledging brood size from 1991 to 1997 was 1.27 ± 0.17 (SD), included a 3-chick brood. Average percent ofYOlmg from 2 study areas, 1991-97 was 11.9 ± 3.23 (SD). We observed renesting up to 3 …


An Update Of The Florida Whooping Crane Release Project Through June 2000, Stephen A. Nesbitt, Martin J. Folk, Kathleen A. Sullivan, Stephen T. Schwikert, Marilyn G. Spalding Jan 2001

An Update Of The Florida Whooping Crane Release Project Through June 2000, Stephen A. Nesbitt, Martin J. Folk, Kathleen A. Sullivan, Stephen T. Schwikert, Marilyn G. Spalding

Proceedings of the North American Crane Workshop

Whooping cranes (Grus americana) reared mostly at the USGS Patuxent Wildlife Research Center (patuxent) or the International Crane Foundation (ICF) have been released in Florida in an effort to reestablish a nonmigratory population in the southeastern United States. From 1993 through spring of 2000, we released 208 cranes. Modifications to the release procedure instituted in 1995 have greatly reduced mortality from the initial release period. First year mortality has averaged 50%. A longterm drought that began after spring 1998 may have contnbuted to increased first year mortality in recent years. Most mortality has been from predation, mostly bobcat …


A Comparison Of Behavior For Two Cohorts Of Captive-Reared Greater Sandhill Cranes Released In Northern Arizona, Daniel P. Mummert, Carol L. Chambers, David H. Ellis Jan 2001

A Comparison Of Behavior For Two Cohorts Of Captive-Reared Greater Sandhill Cranes Released In Northern Arizona, Daniel P. Mummert, Carol L. Chambers, David H. Ellis

Proceedings of the North American Crane Workshop

To determine how the behavior of greater sandhill cranes (Grus canadensis tabida) changes according to time of year, time of day, and number of days after release, we observed the activities of 2 groups of captive-reared greater sandhill cranes at Mormon Lake, northern Arizona. The behaviors we compared were alert, loafing, sleeping, foraging, preening, locomotion, and other. We found costume-reared subadult greater sandhill cranes that were established at the study site for a year spent more time foraging and being alert towards predators than parent -reared juvenile greater sandhill cranes that were recently released from captivity. We also …


Sandhill Crane Nest And Egg Characteristics At Malheur National Wildlife Refuge, Oregon, Carroll D. Littlefield Jan 2001

Sandhill Crane Nest And Egg Characteristics At Malheur National Wildlife Refuge, Oregon, Carroll D. Littlefield

Proceedings of the North American Crane Workshop

For the period 1969-89, greater sandhill crane (Grus canadensis tabida) nest and egg characteristics were assessed for pairs on the Malheur National Wildlife Refuge (Malheur), Oregon. Nests mostly were in broad-fruited burreed (Sparganium eurycarpum) and hardstem bulrush (Scirpus acutus) and were constructed primarily of the same vegetative species that surrounded nests. Averages for nest parameters were diameter 127 xIII cm, crown diameter 77 x 69 cm, bowl diameter 41 x 37 em, bowl depth 5.8 em, nest height 12.4 em, and water depth 25.8 cm. Nests were placed in vegetation with a mean height …


Effects Of An Early Spring Burn On Greater Sandhill Crane Nesting Success At Malheur National Wildlife Refuge, Oregon, Carroll D. Littlefield, John E. Cornely, Bradley D. Ehlers Jan 2001

Effects Of An Early Spring Burn On Greater Sandhill Crane Nesting Success At Malheur National Wildlife Refuge, Oregon, Carroll D. Littlefield, John E. Cornely, Bradley D. Ehlers

Proceedings of the North American Crane Workshop

A 2430 ha prescribed burn was conducted on Malheur National Wildlife Refuge, Harney County, Oregon in March 1985. About 35 days later, 11 greater sandhill crane (Grus canadensis tabida) pairs nested within the burned area; 9 of these hatched. The remaining 2 clutches were destroyed by coyotes (Canis latrans). Crane hatching success was significantly higher (P = 0.01) on the burned area (81.8%) than elsewhere (38.5%). Two factors were likely responsible for the higher success rate in the burn; nests were placed in deeper water and the smaI1 mammal prey base was temporarily reduced or eliminated …


Evaluation Of The Major Histocompatibility Complex (Mhc) In Cranes: Applications To Conservation Efforts, Susan I. Jarvi, Marcia M. Miller, Ronald M. Gotol, George F. Gee, W. Elwood Briles Jan 2001

Evaluation Of The Major Histocompatibility Complex (Mhc) In Cranes: Applications To Conservation Efforts, Susan I. Jarvi, Marcia M. Miller, Ronald M. Gotol, George F. Gee, W. Elwood Briles

Proceedings of the North American Crane Workshop

Although there have been heated discussions concerning the relative importance of using Mhc diversity as a basis for selecting breeders in conservation projects, most parties agree that the genetic variability residual in an endangered species should be maintained through genetic management, if at all possible. Substantial evidence exists (particularly in birds) documenting the influences of specific Mhc haplotypes on disease outcome and also that those individuals which are heterozygous for Mhc alleles appear to have an advantage for survival over those that are homozygous. Thus, conservation of genetic variability of the Mhc is likely important for the preservation of fitness, …


Distribution, Abundance, And Reproduction Of The Cuban Sandhill Crane (Grus Canadensis Nesiotes), Xiomara Galvez Aguilera, Vicente Berovides Alvarez, Jose Rivera Rosales Jan 2001

Distribution, Abundance, And Reproduction Of The Cuban Sandhill Crane (Grus Canadensis Nesiotes), Xiomara Galvez Aguilera, Vicente Berovides Alvarez, Jose Rivera Rosales

Proceedings of the North American Crane Workshop

We discuss the distribution, abundance, and reproduction of the Cuban sandhill crane (Grus canadensis nesiotes). This is an overview of a 5-year study conducted by the National Organization for the Protection of Flora and Fauna of the Ministry of Agriculture for the Republic of Cuba and assisted by the International Crane Foundation and Brehm Fund. The distribution of this subspecies was determined by visiting potential sites and areas where this race has previously been reported. Nine new populations were found. This brings the total to 11 on the Isle of Cuba, 1 on Cayo Romano, and 2 on …


Interactions Of Sandhill Cranes And Whooping Cranes With Foreign Objects In Florida, Martin J. Folk, Stephen A. Nesbitt, Marilyn G. Spalding Jan 2001

Interactions Of Sandhill Cranes And Whooping Cranes With Foreign Objects In Florida, Martin J. Folk, Stephen A. Nesbitt, Marilyn G. Spalding

Proceedings of the North American Crane Workshop

During studies of Florida sandhill cranes (Grus canadensis pralensis), greater sandhill cranes (G. c. tabida), and whooping cranes (G. americana) in Florida, we documented cases where these birds were in contact with human-produced objects that resulted in injury or death. We describe >40 instances in which cranes collided with powerlines or fences, became entangled in string or fishing line, or ingested foreign objects. The effect of human-produced objects on crane populations, particularly small populations, may be significant.


Aquatic Plants Of Nebraska, Michael P. Gutzmer, Robert B. Kaul Jan 2001

Aquatic Plants Of Nebraska, Michael P. Gutzmer, Robert B. Kaul

University of Nebraska State Museum: Programs Information

More than 100 species of aquatic plants grow in Nebraska. Some are entirely submersed for their whole lives, others produce floating leaves and flowers, and still others stand upright, with only their lower stems in water. Examples of these are shown here in this publication.

Vigorous and diverse colonies of aquatic plants are usually a sign of healthy and stable aquatic environments. In fact, the plants themselves stabilize the shorelines, underwater soils, and water chemistry. Waters rich with aquatic plants are rich with aquatic animals and waterfowl, which find cover, breeding habitat, and abundant food. Non-alkaline waters have more aquatic …


Out Of Africa: Origins Of The Taenia Tapeworms In Humans, Eric P. Hoberg, Nancy L. Alkire, Alan De Queiroz, Arlene Jones Jan 2001

Out Of Africa: Origins Of The Taenia Tapeworms In Humans, Eric P. Hoberg, Nancy L. Alkire, Alan De Queiroz, Arlene Jones

Harold W. Manter Laboratory of Parasitology: Faculty Publications

Phylogenetic and divergence date analyses indicate that the occurrence of Taenia tapeworms in humans pre-dates the development of agriculture, animal husbandry and domestication of cattle (Bos spp.) or swine (Sus scrofa) Taeniid tapeworms in Africa twice independently colonized hominids and the genus Homo prior to the origin of modern humans. Dietary and behavioural shifts, from herbivory to scavenging and carnivory, as early Homo entered the carnivore guild in the Pliocene/Pleistocene, were drivers for host switching by tapeworms to hominids from carnivores including hyaenids and felids. Parasitological data provide a unique means of elucidating the historical ecology, foraging behavior …


Hydrologic Events And Water Quality In The Pigeon River, Ottawa County, Michigan, Neil W. Macdonald, Richard R. Rediske, Jonathan E. Van Denend Jan 2001

Hydrologic Events And Water Quality In The Pigeon River, Ottawa County, Michigan, Neil W. Macdonald, Richard R. Rediske, Jonathan E. Van Denend

Peer Reviewed Publications

The Pigeon River drains a 16,765-ha agricultural watershed in western Ottawa County, Michigan and discharges into south-central Lake Michigan. Extensive areas of wetlands in the upper watershed were drained in the 1920s, causing significantly altered hydrology characteristics by flashy discharges during storms and periods of snowmelt. We studied stream chemistry and hydrology for a four-year period between September, 1996, and October, 2000, to determine water quality status, to estimate annual nutrient exports, and to evaluate the effects of different seasonal flow types. Results of our study confirmed that the upper reaches of the Pigeon River experience chronically degraded water quality, …


Twenty-Five Years Of Population Fluctuations Of Microtus Ochrogaster And M-Pennsylvanicus In Three Habitats In East-Central Illinois, Lowell L. Getz, Joyce E. Hofmann, Betty Mcguire, Thomas W. Dolan Iii Jan 2001

Twenty-Five Years Of Population Fluctuations Of Microtus Ochrogaster And M-Pennsylvanicus In Three Habitats In East-Central Illinois, Lowell L. Getz, Joyce E. Hofmann, Betty Mcguire, Thomas W. Dolan Iii

Biological Sciences Faculty Publications

Populations of 2 species of arvicoline rodents, the prairie vole (Microtus ochrogaster) and meadow vole (M. pennsylvanicus), were monitored monthly in alfalfa, bluegrass, and tallgrass prairie habitats in east-central Illinois from 1972 through 1997. Alfalfa provides very highquality preferred food and poor vegetative cover for both vole species, whereas bluegrass provides intermediate food and vegetative cover. Preferred food resources were very low, especially for M. ochrogaster, and vegetative cover was very dense in tallgrass prairie. Maximum and mean population densities of M. ochrogaster were highest in alfalfa, intermediate in bluegrass, and lowest in tallgrass prairie. …


Perceived Damage By Elk In The Arkansas Ozarks, Jennifer H. Herner-Thogmartin, Kimberly G. Smith, Michael E. Cartwright Jan 2001

Perceived Damage By Elk In The Arkansas Ozarks, Jennifer H. Herner-Thogmartin, Kimberly G. Smith, Michael E. Cartwright

Journal of the Arkansas Academy of Science

Wildlife managers in Arkansas are faced with managing a growing population of Rocky Mountain elk (Cervus elaphus neloni) that has extended its range to incorporate private lands near the Buffalo National River (BNR) in northcentral Arkansas. This range expansion has created conflicts between private landowners and wildlife management personnel. To document the extent of damage and assess attitudes of landowners with elk on their land, interviews were conducted with landowners who contacted us or the Arkansas Game and Fish Commission about problems with elk. A survey also was created and sent to landowners who live near the BNR in Boone …


Breeding Season Distribution Of Cerulean Warblers In Arkansas In The 1990s, Douglas A. James, Christopher J. Kellner, Jan Self, Jerry Davis Jan 2001

Breeding Season Distribution Of Cerulean Warblers In Arkansas In The 1990s, Douglas A. James, Christopher J. Kellner, Jan Self, Jerry Davis

Journal of the Arkansas Academy of Science

The Cerulean Warbler (Dendroica cerulea) has been declining in numbers in its North American nesting range, and the same is true in Arkansas. To provide specific sites that can be monitored in the future, this study describes places where the bird was documented in the state in the 1990s. The warbler was found in mature deciduous forest in both upland and bottomland situations but was most abundant in the upland Ozark forests and uncommon in other regions of the state. Most (70%) of the occupied sites were on federal and state lands. Pattern of overall distribution was essentially the same …


Effects Of Fish Culture On Macrobenthos Diversity And Abundance In The Matang Mangrove Estuary (Malaysia), Patricia Natin Jan 2001

Effects Of Fish Culture On Macrobenthos Diversity And Abundance In The Matang Mangrove Estuary (Malaysia), Patricia Natin

Student Works (2000-2009)

A study on the effects of fish cage culture on mangrove macrobenthos diversity and abundance was carried out in the Matang mangrove estuary, Perak, Malaysia. Multiple investigations consisted of 4-month study, 12-hour study and I-day "grid" sampling. Six samplings (Dec 1999 - May 2000) were conducted along Sungai (River) Sangga Besar (SSB) (cage culture area) and Sungai Sangga Kecil (SSK) (non-cage culture area) by using a 0.1 m² Petersen Grab, Forty-four families (I nemertean, 12 polychaete, 5 bivalve, 11 gastropod, 7 decapod, 2 isopod, 2 amphipod, I ophiuroid and 3 fishes), comprising of 53 species were found, which increased in …


Diversity And Abundance Of Seaweeds On The Coral Reef Flats At Cape Rachado, West Coast Peninsular Malaysia, Jillian Lean Sim Ooi Jan 2001

Diversity And Abundance Of Seaweeds On The Coral Reef Flats At Cape Rachado, West Coast Peninsular Malaysia, Jillian Lean Sim Ooi

Student Works (2000-2009)

Three sites on the fringing coral reef flats at Cape Rachado, West Coast Peninsular Malaysia, were selected for the study of seaweed diversity and abundance. Each of these sites was identifiable with exposure to a particular environmental stress. Site A suffered from heavy loads of total suspended solids (TSS) caused by the removal of its adjoining coastal mangrove stand. Site B, by virtue of its accessibility and location on a popular stretch of beach, received a greater number of swimmers and beachwalkers. Water effluent (sewage) outlets from the various resorts lining the coast were observed at sites A and B. …


Diversity And Abundance Of Phytoplankton In Tasek Bera, Pahang, Soo Hui Tang Jan 2001

Diversity And Abundance Of Phytoplankton In Tasek Bera, Pahang, Soo Hui Tang

Student Works (2000-2009)

Tasek Bera, located in southwest of Pahang state, is Malaysia's largest freshwater swamp and lake system. It is one of the remaining examples of a lowland alluvial riparian swamp system. Tasek Bera was designated as Malaysia's first "Wetlands of International Importance" under the Ramsar Convention in November 1994. The water quality of Tasek Bera was monitored from April to October 1998 to assess environmental conditions affecting phytoplankton assemblages. Measurement of physical and chemical parameters at selected sites ranged as follows : pH (4.45 to 6.73), temperature (25.3 to 33.3 °C), dissolved oxygen (0.40 to 5.80 mgL⁻¹), water depth (0.15 to …


Investigations On The Environmental Significance And The Bioavailability Of Heavy Metals In Soils, Inaam Ali Abdallah Saad Jan 2001

Investigations On The Environmental Significance And The Bioavailability Of Heavy Metals In Soils, Inaam Ali Abdallah Saad

Student Works (2000-2009)

Heavy metals contaminated soils pose a continuing and increasing threat to human health, the increased inputs of heavy metals from the widespread disposal of industrial wastes have created an Increased attention on the issue of their fate. bioavailability and environmental significance. These Investigations were carried mainly to study the solid - solution phase distribution, chemical speciation and plant uptake of cadmium (Cd), lead (Pb), nickel (Ni) and zinc (Zn) in three contrasting soils amended with Cd, Pb. Ni and Zn nitrate sails at rates of 5-40 mmol/kg for incubation time varied between 3-15 month. Although heavy metal cations adsorbed to …


Way-Finding And Landmarks: The Multiple Bearings Hypothesis, Alan C. Kamil, Ken Cheng Jan 2001

Way-Finding And Landmarks: The Multiple Bearings Hypothesis, Alan C. Kamil, Ken Cheng

Papers in Behavior in Biological Sciences

Clark’s nutcrackers (Nucifraga columbiana) are capable of very precise searching using the metric relationships between a goal and multiple landmarks to relocate the goal location. They can judge the direction more accurately than the distance to a landmark when the landmark is distant from the goal. On the basis of these findings, we propose that nutcrackers use a set of bearings, each a measure of the direction from the goal to a different landmark, when searching for that goal. The results of a simulation demonstrate that increasing the number of landmarks used results in increasingly precise searching. This …


Review Of Evolution And Cognition, Edited By Cecilia Heyes And Ludwig Huber., Alan Kamil Jan 2001

Review Of Evolution And Cognition, Edited By Cecilia Heyes And Ludwig Huber., Alan Kamil

Papers in Behavior in Biological Sciences

Heyes and Huber have edited a volume that surveys much of the current research into cognition in animals, reflecting the strengths and weaknesses of this field. The book is divided into five sections. In the first part, titled “Orientations,” four authors lay out their basic general views of the field. The first two chapters in this section are by the editors. First, Heyes makes the case for an approach to evolutionary psychology that she labels “in the round,” an approach that would encompass studies of human and nonhuman animals alike and include a broad range of contemporary evolutionary approaches. This …


Chondrocranium And Visceral Skeleton Of Atelopus Tricolor And Atelophryniscus Chrysophorus, E O. Lavilla, Rafael O. De Sá Jan 2001

Chondrocranium And Visceral Skeleton Of Atelopus Tricolor And Atelophryniscus Chrysophorus, E O. Lavilla, Rafael O. De Sá

Biology Faculty Publications

Atelopus tricolor and Atelophryniscus chrysophorus have gastromyzophorous tadpoles. Aside from specific differences, the larval chondrocrania and visceral skeletons show several shared character states, including an almost quadrangular, open chondrocranium , cornua trabeculae with expanded tips, cartilago suprarostralis as a single element, a posteriorly projected arcus subocularis quadrati, a closed muscular tunnel, and a simplified branchial basket, with only three pairs of ceratobranchiales. They are compared with diverse character states of suctorial larvae considering them as causally related to the stream life adaptations.


Managing Wetland Vegetation For Marsh Birds And Waterfowl At Carlyle Lake Wildlife Management Area, Il, Matthew W. Bowyer Jan 2001

Managing Wetland Vegetation For Marsh Birds And Waterfowl At Carlyle Lake Wildlife Management Area, Il, Matthew W. Bowyer

Masters Theses

The high cost of restoring and managing wetlands warrants careful assessment of their management potential. We designed this study to provide basic information on how seed banks and hydroperiod influence the development of habitat for migratory birds in restored wetlands at Carlyle Lake Wildlife Management Area (CLWMA). The objectives were to: (1) survey the composition of the seed banks; (2) investigate the effects of early- vs. late-drawdowns on the germination and growth of these plants; and (3) monitor the use of these communities by wetland birds during migration and the breeding season. The study was conducted on a marsh complex …


Isolation Effects Of Aquatic Habitat Fragmentation On Greenside (Etheostoma Blennioides) And Fantail (Etheostoma Flabellare) Darters, Rita M. Klein Jan 2001

Isolation Effects Of Aquatic Habitat Fragmentation On Greenside (Etheostoma Blennioides) And Fantail (Etheostoma Flabellare) Darters, Rita M. Klein

Masters Theses

Aquatic habitat fragmentation is defined as the lack of connectivity between upstream and downstream populations and can occur along two gradients, the longitudinal gradient and the lateral gradient. The longitudinal gradient focuses on objects within the stream and is concerned with the disruption of stream flow, which is normally brought about by the presence of dams and bridges. Fragmentation along the lateral gradient, on the other hand, examines factors outside of the stream and is related to any loss or modification of the surrounding riparian zone.

In Illinois within the last 100 years, stream habitats have become increasingly fragmented by …


Hydrogeological Characterization Of The South Oyster Bacterial Transport Site Using Geophysical Data, Susan S. Hubbard, Jinsong Chen, John Peterson, Ernest L. Majer, Kenneth H. Williams, Donald J. Swift, Brian Mailloux, Yoram Rubin Jan 2001

Hydrogeological Characterization Of The South Oyster Bacterial Transport Site Using Geophysical Data, Susan S. Hubbard, Jinsong Chen, John Peterson, Ernest L. Majer, Kenneth H. Williams, Donald J. Swift, Brian Mailloux, Yoram Rubin

OES Faculty Publications

A multidisciplinary research team has conducted a field-scale bacterial transport study within an uncontaminated sandy Pleistocene aquifer near Oyster, Virginia. The overall goal of the project was to evaluate the importance of heterogeneities in controlling the field-scale transport of bacteria that are injected into the ground for remediation purposes. Geochemical, hydrological, geological, and geophysical data were collected to characterize the site prior to conducting chemical and bacterial injection experiments. In this paper we focus on results of a hydrogeological characterization effort using geophysical data collected across a range of spatial scales. The geophysical data employed include surface ground-penetrating radar, radar …


Growth Rate Variability And Lipofuscin Accumulation Rates In The Blue Crab Callinectes Sapidus, Se-Jong Ju, David H. Secor, H. Rodger Harvey Jan 2001

Growth Rate Variability And Lipofuscin Accumulation Rates In The Blue Crab Callinectes Sapidus, Se-Jong Ju, David H. Secor, H. Rodger Harvey

OES Faculty Publications

To better understand growth and age-pigment (lipofuscin) accumulation rates of the blue crab Callinectes sapidus under natural conditions, juveniles (33 to 94 mm carapace width) were reared in outdoor ponds for over 1 yr. Growth rates, measured by carapace width, during summer and fall exceeded all those reported in the literature; the initial carapace width of 59 ± 14 mm (mean ± SD) increased to 164 ± 15 mm within a 3 mo period. No growth occurred during winter months (November to April) at low water temperatures. Growth rates of crabs in ponds were substantially higher (von Bertalanffy growth parameter …


A New Species Of Marsupial Frog (Anura: Hylidae: Gastrotheca), Edgar Lehr, William Duellman, Cesar Aguilar Jan 2001

A New Species Of Marsupial Frog (Anura: Hylidae: Gastrotheca), Edgar Lehr, William Duellman, Cesar Aguilar

Scholarship

A new species of Gastrotheca from the southern end of the Cordillera Azul in Peru seems to be most closely related to G. lateollota known only from the Cordillera Huancabamba in northern Peru. Both of these species and G. marsupiata, monticola and peruana produce tadpoles, whereas the other species of Gastrotheea in Peruvian Andes have direct development.


Managing Minnesota's Recovered Wolves, L. David Mech Jan 2001

Managing Minnesota's Recovered Wolves, L. David Mech

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

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 …