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2001

Series

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Articles 1 - 16 of 16

Full-Text Articles in Physical Sciences and Mathematics

Intermediate Rings Between A Local Domain And Its Completion, Ii, William Heinzer, Christel Rotthaus, Sylvia Wiegand Oct 2001

Intermediate Rings Between A Local Domain And Its Completion, Ii, William Heinzer, Christel Rotthaus, Sylvia Wiegand

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

We present results connecting flatness of extension rings to the Noetherian property for certain intermediate rings between an excellent normal local domain and its completion. We consider conditions for these rings to have Cohen-Macaulay formal fibers. We also present several examples illustrating these results.

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Effects Of Fire Ants (Hymenoptera: Formicidae) On Hatching Turtles And Prevalence Of Fire Ants On Sea Turtle Nesting Beaches In Florida, Craig R. Allen, Elizabeth A. Forys, Kenneth G. Rice, Daniel P. Wojcik Jan 2001

Effects Of Fire Ants (Hymenoptera: Formicidae) On Hatching Turtles And Prevalence Of Fire Ants On Sea Turtle Nesting Beaches In Florida, Craig R. Allen, Elizabeth A. Forys, Kenneth G. Rice, Daniel P. Wojcik

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Red imported fire ants (Solenopsis invicta Buren) have increasingly been observed in loggerhead (Caretta caretta L.) and green (Chelonia mydas L.) sea turtle nests in Florida, and in the nests of freshwater turtles. They may be attracted to the disturbance, mucous and moisture associated with turtle nesting and establish foraging tunnels into turtle nests shortly after egg-laying, thus increasing the vulnerability of hatchlings to fire ant predation. We conducted experiments on a freshwater turtle (Pseudemys nelsoni Carr) to determine the potential impacts of S.invicta on turtle hatchlings. Over 70% of hatchlings were killed by S.invicta during …

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The Non-Indigenous Ant, Solenopsis Invicta, Reduces Loggerhead Shrike And Native Insect Abundance, Craig R. Allen, R. Scott Lutz, Tim Lockley, Sherman A. Phillips Jr., Stephen Demarais Jan 2001

The Non-Indigenous Ant, Solenopsis Invicta, Reduces Loggerhead Shrike And Native Insect Abundance, Craig R. Allen, R. Scott Lutz, Tim Lockley, Sherman A. Phillips Jr., Stephen Demarais

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

The red imported fire ant (Solenopsis invicta Buren) is an aggressive, non-indigenous species that is a threat to native biota in the southeastern United States. We determined the effect of S. invicta on loggerhead shrike (Lanius ludovicianus L.) abundance and investigated a possible mechanism of impact, which is a reduction in insect prey availability. We used a fire ant bait (hydramethylnon) to reduce fire ant populations on one randomly chosen member of each of five pairs of 202-ha study areas in the Texas coastal Bend region, and also measured shrike relative abundance and a volumetric index of insect …

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Potential Fire Ant (Hymenoptera: Formicidae) Impact On The Endangered Schaus Swallowtail (Lepidoptera: Papilionidae), Elizabeth A. Forys, Anna Quistorff, Craig R. Allen Jan 2001

Potential Fire Ant (Hymenoptera: Formicidae) Impact On The Endangered Schaus Swallowtail (Lepidoptera: Papilionidae), Elizabeth A. Forys, Anna Quistorff, Craig R. Allen

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

The Schaus swallowtail, Papilio aristodemus ponceanus , historically occurred in tropical hardwood hammocks from South Miami to the upper Florida Keys and is currently listed as federally endangered. Much of the remaining hardwood hammock habitat is fragmented by roads and human development that may alter the microhabitat within the hammocks and increase the probability of invasion by non-native predators and competitors. One non-indigenous species that has recently invaded the Florida Keys, and that may impact the Schaus swallowtail is the red imported fire ant ( Solenopsis invicta Buren). We estimated abundance of red imported fire ants in Schaus swallowtail habitat …

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Effects Of Fire Ants (Hymenoptera: Formicidae) On Hatching Turtles And Prevalence Of Fire Ants On Sea Turtle Nesting Beaches In Florida, Craig R. Allen, Elizabeth A. Forys, Kenneth G. Rice, Daniel P. Wojcik Jan 2001

Effects Of Fire Ants (Hymenoptera: Formicidae) On Hatching Turtles And Prevalence Of Fire Ants On Sea Turtle Nesting Beaches In Florida, Craig R. Allen, Elizabeth A. Forys, Kenneth G. Rice, Daniel P. Wojcik

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Red imported fire ants (Solenopsis invicta Buren) have increasingly been observed in loggerhead (Caretta caretta L.) and green (Chelonia mydas L.) sea turtle nests in Florida, and in the nests of freshwater turtles. They may be attracted to the disturbance, mucous and moisture associated with turtle nesting and establish foraging tunnels into turtle nests shortly after egg-laying, thus increasing the vulnerability of hatchlings to fire ant predation. We conducted experiments on a freshwater turtle (Pseudemys nelsoni Carr) to determine the potential impacts of S.invicta on turtle hatchlings. Over 70% of hatchlings were killed by S.invicta during …

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The Likely Cause Of Extinction Of The Tree Snail Orthalicus Reses Reses (Say), E.A. Forys, A. Quistorff, Craig R. Allen, D.P. Wojcik Jan 2001

The Likely Cause Of Extinction Of The Tree Snail Orthalicus Reses Reses (Say), E.A. Forys, A. Quistorff, Craig R. Allen, D.P. Wojcik

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

The Stock Island tree snail, Orthalicus reses reses, went extinct in its native range in the Florida Keys in 1992. Fortunately, O. r. reses has been introduced elsewhere and further reintroductions are currently planned. Before these reintroductions are implemented, it is important to try and determine which factors were most likely to have caused the decline and extinction. While habitat destruction was probably the ultimate reason why there were so few tree snails, it is likely that an interaction of habitat fragmentation and the invasion of an exotic predator caused the final decline that lead to the extinction in …

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Red Imported Fire Ants: Impact On Biodiversity, Daniel P. Wojcik, Craig R. Allen, Richard J. Brenner, Elizabeth A. Forys, Donald P. Jouvenaz, R. Scott Lutz Jan 2001

Red Imported Fire Ants: Impact On Biodiversity, Daniel P. Wojcik, Craig R. Allen, Richard J. Brenner, Elizabeth A. Forys, Donald P. Jouvenaz, R. Scott Lutz

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

The red imported fire ant, Solenopsis invicta Buren (hereafter referred to as imported fire ant), long considered a regional problem, is receiving renewed attention nationwide, with infestations found in Arizona, Maryland, Nevada, New Mexico, and Virginia (Mitchell 1996). Recently, infestations discovered in several regions of California caused great public concern (Brennan 1999, Schrader 1999). Initially, infestations appeared to be isolated in almond groves in Kern County; presumably these infestations originated from bee hives transported interstate for the purpose of pollinating crops. Separately, ornamental plants arriving in Las Vegas, NV, were infested with fire ants, and records showed that the point …

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Nonlethal Methods Of Examining Fish Stomach Contents, Jan F. Kamler, Kevin L. Pope Jan 2001

Nonlethal Methods Of Examining Fish Stomach Contents, Jan F. Kamler, Kevin L. Pope

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Several nonlethal methods have been developed to determine the stomach contents of fish, including gastroscopes, tubes, stomach suction, stomach flushing, emetics, forceps, and chronic fistulas. By reviewing the literature on this subject, we found that the effectiveness (ability to remove all stomach contents) of the different methods depends on size, age, species of fish, and the size of the food items in the stomach. Overall, various methods of stomach flushing were the most effective method of recovering stomach items from a variety of fishes. Mechanized pressure appeared to be the most efficient method of stomach flushing for most large fishes. …

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A Caloric-Based Evaluation Of Diet Indices For Largemouth Bass, Kevin Lee Pope, Michael Lee Brown, Walter Gilbert Duffy, Paul Herbert Michaletz Jan 2001

A Caloric-Based Evaluation Of Diet Indices For Largemouth Bass, Kevin Lee Pope, Michael Lee Brown, Walter Gilbert Duffy, Paul Herbert Michaletz

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Selection of methods for quantitative description and assessment of food habits is a concern for trophic investigations. We used diet data for largemouth bass Micropterus salmoides, to compare a caloric-based approach with eight diet indices: percent frequency of occurrence, percent total number, percent total weight, mean relative number, mean relative volume, relative importance index, prey-importance index, and mean stomach fullness. Mean caloric contribution of stomach contents for each prey taxon was used as a standard to compare diet indices. Temporal differences in composition and caloric contents of largemouth bass stomach contents were apparent. Most diet indices provided similar assessments …

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Assessment Of Outputs From Smith-Root Model-5.0 Gpp And Model-7.5 Gpp Electrofishers, Kevin L. Pope, Brian E. Van Zee, Michael C. Mayo, Mohammed Rahman Jan 2001

Assessment Of Outputs From Smith-Root Model-5.0 Gpp And Model-7.5 Gpp Electrofishers, Kevin L. Pope, Brian E. Van Zee, Michael C. Mayo, Mohammed Rahman

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

We evaluated the outputs from eight Smith-Root electrofishers (two factory-rigged model-5.0 GPP boats, four biologist-rigged model-5.0 GPP boats, and two biologist-rigged model- 7.5 GPP boats), using an oscilloscope to determine the actual waveforms (voltage as a function of time), current, and power produced for various settings. Differences were found in average power outputs among the six model-5.0 GPP electrofishing boats. In terms of average power output, biologist-rigged electrofishing boats using generators and control boxes purchased from Smith-Root were as or more effective than those rigged by Smith-Root. However, factory-rigged boats generally contained additional safety features that should be considered when …

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Anglers Tagging And Marking Fish: Provincial And State Fishery Agency Views, Kevin L. Pope Jan 2001

Anglers Tagging And Marking Fish: Provincial And State Fishery Agency Views, Kevin L. Pope

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

In recent years, the involvement of anglers in fish tagging programs has begun to capture the interest of managers. I conducted a mail survey of provincial and state fishery agencies to discern where anglers could legally tag, mark, or attach telemetry devices to fish. In addition, I documented current provincial and state agency views toward fish tagging or marking by anglers. Anglers were allowed to tag or mark fish in most provinces and states; however, more restrictions were placed on marking and telemetering fish than on tagging. Of the issues covered in this survey, respondents indicated that fish mortality and …

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Yellow Jackets (Vespula Spp.) Disperse Trillium (Spp.) Seeds In Eastern North America, Jennifer A. Zettler, Timonthy P. Spira, Craig R. Allen Jan 2001

Yellow Jackets (Vespula Spp.) Disperse Trillium (Spp.) Seeds In Eastern North America, Jennifer A. Zettler, Timonthy P. Spira, Craig R. Allen

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Approximately 70 plant families worldwide have ant-dispersed seeds (myrmecochory). In this putative ant-plant mutualism, ants are attracted to and disperse seeds that have a lipid-rich elaiosome. We observed yellow jackets (Vespula spp.) dispersing seeds of three elaiosome-bearing species-Trillium cuneatum, T. undulatum and T catesbaei-in the Blue Ridge Mountains of North Carolina and South Carolina. Moreover, we estimated the mean distance yellow jackets dispersed seeds of T. cuneatum by placing intact fruits on index cards and recovering dispersed seeds on sheets placed on the ground surface. Of the seeds presented, 41% were recovered and the average dispersal distance …

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Ant–Seed Mutualisms: Can Red Imported Fire Ants Sour The Relationship?, Jennifer A. Zettler, Timothy P. Spira, Craig R. Allen Jan 2001

Ant–Seed Mutualisms: Can Red Imported Fire Ants Sour The Relationship?, Jennifer A. Zettler, Timothy P. Spira, Craig R. Allen

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Invasion by the red imported fire ant, Solenopsis invicta, has had negative impacts on individual animal and plant species, but little is known about how S. invicta affects complex mutualistic relationships. In some eastern forests of North America, 30% of herbaceous species have ant-dispersed seeds. We conducted experiments to determine if fire ants are attracted to seeds of these plant species and assessed the amount of scarification or damage that results from handling by fire ants. Fire ants removed nearly 100% of seeds of the ant-dispersed plants Trillium undulatum, T. discolor, T. catesbaei, Viola rotundifolia, and Sanguinaria canadensis. …

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Modeling Viable Mammal Populations In Gap Analyses, Craig R. Allen, L. G. Pearlstine Jan 2001

Modeling Viable Mammal Populations In Gap Analyses, Craig R. Allen, L. G. Pearlstine

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Gap analysis is an approach to conserving biological diversity that maps species richness and identifies sites that ought to be protected but are not in conservation networks. Gap analyses based on species richness may have high error rates when species models are based solely on species-habitat association, because patches too small to support populations are still considered to be potential habitat. We incorporated information on the home range and dispersal distances of the mammals of Florida to estimate minimum critical areas (MCA) to support minimum viable populations for each mammal species. Incorporating MCA decreases the area occupied by the highest …

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Potential Fire Ant (Hymenoptera: Formicidae) Impact On The Endangered Schaus Swallowtail (Lepidoptera: Papilionidae), Elizabeth A. Forys, Anna Quistorff, Craig R. Allen Jan 2001

Potential Fire Ant (Hymenoptera: Formicidae) Impact On The Endangered Schaus Swallowtail (Lepidoptera: Papilionidae), Elizabeth A. Forys, Anna Quistorff, Craig R. Allen

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

The Schaus swallowtail, Papilio aristodemus ponceanus, historically occurred in tropical hardwood hammocks from South Miami to the upper Florida Keys and is currently listed as federally endangered. Much of the remaining hardwood hammock habitat is fragmented by roads and human development that may alter the microhabitat within the hammocks and increase the probability of invasion by non-native predators and competitors. One non-indigenous species that has recently invaded the Florida Keys, and that may impact the Schaus swallowtail is the red imported fire ant (Solenopsis invicta Buren). We estimated abundance of red imported fire ants in Schaus swallowtail habitat …

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The Spatial Distribution Of Diversity Between Disparate Taxa: Spatial Correspondence Between Mammals And Ants Across South Florida, Usa, Craig R. Allen, L. G. Pearlstine, D.P. Wojcik, W.M. Kitchens Jan 2001

The Spatial Distribution Of Diversity Between Disparate Taxa: Spatial Correspondence Between Mammals And Ants Across South Florida, Usa, Craig R. Allen, L. G. Pearlstine, D.P. Wojcik, W.M. Kitchens

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Gap Analysis takes a proactive landscape-level approach to conserving native species by identifying nodes of high biological diversity. It uses vertebrate species richness as an index of overall biological diversity. However, it remains unknownwhether or not the spatial distribution of vertebrate diversity correspondswith the diversity of other taxa. We tested whether landscape-level diversity patterns corresponded between a vertebrate and an invertebrate taxon, mammals and ants, across the southern half of the Florida peninsula, USA. Composite digital maps with a 30-m spatial resolution were produced for each taxon. Spatial correspondence between the taxa was determined by normalizing and then subtracting the …

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