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- Abundance of horseshoe crabs (Limulus polyphemus) in the Delaware Bay areaHata, David; Berkson, James M. (National Marine Fisheries Service Scientific Publication Office, 2003-10)Discusses a study on horseshoe crabs in the vicinity of Delaware Bay. Abundance of horseshoe crabs in the area; Factor that influenced horseshoe crab catchability; Mean abundance estimate for all crabs.
- Agroforestry in Appalachia-Laurel Fork SapsuckersHammett, A. L. (Tom) (2023)
- Biological Earth observation with animal sensorsJetz, Walter; Tertitski, Grigori; Kays, Roland; Mueller, Uschi; Wikelski, Martin; Akesson, Susanne; Anisimov, Yury; Antonov, Aleksey; Arnold, Walter; Bairlein, Franz; Balta, Oriol; Baum, Diane; Beck, Mario; Belonovich, Olga; Belyaev, Mikhail; Berger, Matthias; Berthold, Peter; Bittner, Steffen; Blake, Stephen; Block, Barbara; Bloche, Daniel; Boehning-Gaese, Katrin; Bohrer, Gil; Bojarinova, Julia; Bommas, Gerhard; Bourski, Oleg; Bragin, Albert; Bragin, Alexandr; Bristol, Rachel; Brlik, Vojtech; Bulyuk, Victor; Cagnacci, Francesca; Carlson, Ben; Chapple, Taylor K.; Chefira, Kalkidan F.; Cheng, Yachang; Chernetsov, Nikita; Cierlik, Grzegorz; Christiansen, Simon S.; Clarabuch, Oriol; Cochran, William; Cornelius, Jamie Margaret; Couzin, Iain; Crofoot, Margret C.; Cruz, Sebastian; Davydov, Alexander; Davidson, Sarah; Dech, Stefan; Dechmann, Dina; Demidova, Ekaterina; Dettmann, Jan; Dittmar, Sven; Dorofeev, Dmitry; Drenckhahn, Detlev; Dubyanskiy, Vladimir; Egorov, Nikolay; Ehnbom, Sophie; Ellis-Soto, Diego; Ewald, Ralf; Feare, Chris; Fefelov, Igor; Fehervari, Peter; Fiedler, Wolfgang; Flack, Andrea; Froboese, Magnus; Fufachev, Ivan; Futoran, Pavel; Gabyshev, Vyachaslav; Gagliardo, Anna; Garthe, Stefan; Gashkov, Sergey; Gibson, Luke; Goymann, Wolfgang; Gruppe, Gerd; Guglielmo, Chris; Hartl, Phil; Hedenstrom, Anders; Hegemann, Arne; Heine, Georg; Ruiz, Maggi Hieber; Hofer, Heribert; Huber, Felix; Hurme, Edward; Iannarilli, Fabiola; Illa, Marc; Isaev, Arkadiy; Jakobsen, Bent; Jenni, Lukas; Jenni-Eiermann, Susi; Jesmer, Brett R.; Jiguet, Frederic; Karimova, Tatiana; Kasdin, N. Jeremy; Kazansky, Fedor; Kirillin, Ruslan; Klinner, Thomas; Knopp, Andreas; Koelzsch, Andrea; Kondratyev, Alexander; Krondorf, Marco; Ktitorov, Pavel; Kulikova, Olga; Kumar, R. Suresh; Kuenzer, Claudia; Larionov, Anatoliy; Larose, Christine; Liechti, Felix; Linek, Nils; Lohr, Ashley; Lushchekina, Anna; Mansfield, Kate; Matantseva, Maria; Markovets, Mikhail; Marra, Peter; Masello, Juan F.; Melzheimer, Joerg; Menz, Myles HM M.; Menzie, Stephen; Meshcheryagina, Swetlana; Miquelle, Dale; Morozov, Vladimir; Mukhin, Andrey; Mueller, Inge; Mueller, Thomas; Navedo, Juan G.; Nathan, Ran; Nelson, Luke; Nemeth, Zoltan; Newman, Scott; Norris, Ryan; Nsengimana, Olivier; Okhlopkov, Innokentiy; Oles, Wioleta; Oliver, Ruth; O'Mara, Teague; Palatitz, Peter; Partecke, Jesko; Pavlick, Ryan; Pedenko, Anastasia; Perry, Alys; Pham, Julie; Piechowski, Daniel; Pierce, Allison; Piersma, Theunis; Pitz, Wolfgang; Plettemeier, Dirk; Pokrovskaya, Irina; Pokrovskaya, Liya; Pokrovsky, Ivan; Pot, Morrison; Prochazka, Petr; Quillfeldt, Petra; Rakhimberdiev, Eldar; Ramenofsky, Marilyn; Ranipeta, Ajay; Rapczynski, Jan; Remisiewicz, Magdalena; Rozhnov, Viatcheslav; Rienks, Froukje; Rozhnov, Vyacheslav; Rutz, Christian; Sakhvon, Vital; Sapir, Nir; Safi, Kamran; Schaeuffelhut, Friedrich; Schimel, David; Schmidt, Andreas; Shamoun-Baranes, Judy; Sharikov, Alexander; Shearer, Laura; Shemyakin, Evgeny; Sherub, Sherub; Shipley, Ryan; Sica, Yanina; Smith, Thomas B.; Simonov, Sergey; Snell, Katherine; Sokolov, Aleksandr; Sokolov, Vasiliy; Solomina, Olga; Spina, Fernando; Spoelstra, Kamiel; Storhas, Martin; Sviridova, Tatiana; Swenson, George; Taylor, Phil; Thorup, Kasper; Tsvey, Arseny; Tucker, Marlee; Tuppen, Sophie; Turner, Woody; Twizeyimana, Innocent; van der Jeugd, Henk; van Schalkwyk, Louis; van Toor, Marielle; Viljoen, Pauli; Visser, Marcel E.; Volkmer, Tamara; Volkov, Andrey; Volkov, Sergey; Volkov, Oleg; von Ronn, Jan AC C.; Vorneweg, Bernd; Wachter, Bettina; Waldenstrom, Jonas; Weber, Natalie; Wegmann, Martin; Wehr, Aloysius; Weinzierl, Rolf; Weppler, Johannes; Wilcove, David; Wild, Timm; Williams, Hannah J.; Wilshire, John H.; Wingfield, John; Wunder, Michael; Yachmennikova, Anna; Yanco, Scott; Yohannes, Elisabeth; Zeller, Amelie; Ziegler, Christian; Ziecik, Anna; Zook, Cheryl (Cell Press, 2022-05-22)Space-based tracking technology using low-cost miniature tags is now delivering data on fine-scale animal movement at near-global scale. Linked with remotely sensed environmental data, this offers a biological lens on habitat integrity and connectivity for conservation and human health; a global network of animal sentinels of environmental change.
- Biological Earth observation with animal sensorsJetz, Walter; Tertitski, Grigori; Kays, Roland; Mueller, Uschi; Wikelski, Martin; Supporting authors; Jesmer, Brett R. (Elsevier, 2022-04-01)Space-based tracking technology using low-cost miniature tags is now delivering data on fine-scale animal movement at near-global scale. Linked with remotely sensed environmental data, this offers a biological lens on habitat integrity and connectivity for conservation and human health; a global network of animal sentinels of environmental change.
- Branching Out: Alternative Tree Saps Integrated with AgroforestryHammett, A. L. (Tom) (2023)
- Can The Size of a Fish Mother Determine the Size of Her Offspring?Hamel, Emily M.; Roethler, Margaret G.; Tremewan, Caitlin A.; Kindsvater, Holly K. (Frontiers, 2022-04-19)What affects the size and health of fish babies? The size of a young fish may strongly influence its chance of survival after hatching, so it is important to understand why fish are born in the condition they are. One answer could be the age and size of the mother, but this has been hard to study in the wild. Sheepshead swordtail females carry their eggs until the baby fish are born swimming. Therefore, since most of the growing happens inside the mother, her offspring can only grow so big. This means that scientists can determine the condition of the babies by trapping the mother and measuring her age and size. Our research group used sheepshead swordtails to check if a mother’s age and size affects the size and health of her offspring. We found that larger, older swordtails produce larger offspring!
- Climate characteristics of the Big Levels region, Augusta County, VirginiaKlopfer, Scott D. (Virginia Natural History Society, 1999)
- Comparison of benthic macroinvertebrate assessment methods along a salinity gradient in headwater streamsPence, Rachel A.; Cianciolo, Thomas R.; Drover, Damion R.; McLaughlin, Daniel L.; Soucek, David J.; Timpano, Anthony J.; Zipper, Carl E.; Schoenholtz, Stephen H. (Springer, 2021-12-01)Benthic macroinvertebrate community assessments are used commonly to characterize aquatic systems and increasingly for identifying their impairment caused by myriad stressors. Yet sampling and enumeration methods vary, and research is needed to compare their abilities to detect macroinvertebrate community responses to specific water quality variables. A common assessment method, rapid bioassessment, uses subsampling procedures to identify a fixed number of individual organisms regardless of total sample abundance. In contrast, full-enumeration assessments typically allow for expanded community characterization resulting from higher numbers of identified organisms within a collected sample. Here, we compared these two sampling and enumeration methods and their abilities to detect benthic macroinvertebrate response to freshwater salinization, a common stressor of streams worldwide. We applied both methods in headwater streams along a salinity gradient within the coal-mining region of central Appalachia USA. Metrics of taxonomic richness, community composition, and trophic function differed between the methods, yet most metrics exhibiting significant response to SC for full-enumeration samples also did for rapid bioassessment samples. However, full-enumeration yielded taxonomic-based metrics consistently more responsive to the salinization gradient. Full-enumeration assessments may potentially provide more complete characterization of macroinvertebrate communities and their response to increased salinization, whereas the more cost-effective and widely employed rapid bioassessment method can detect community alterations along the full salinity gradient. These findings can inform decisions regarding such tradeoffs for assessments of freshwater salinization in headwater streams and highlight the need for similar research of sampling and enumeration methodology in other aquatic systems and for other stressors.
- Compassionately Hidden: The Church Telling Local Homeless to “Come to Our House"Oliver, Robert D.; Robinson, Matthew; Koebel, C. Theodore (Gamma Theta Upsilon, 2015)In early 2011, the To Our House (TOH) thermal shelter program opened its doors to homeless men in the New River Valley Area (NRV) of Virginia. The program was a grass roots response to the death of a well-known local homeless man and the goal of the program is to provide winter shelter for single adult men by using rotating host sites at local churches. We highlight that in the NRV local churches have sought to remedy a socially unjust situation by providing shelter for men that was previously unavailable. We illustrate that faith-based outreach in the New River Valley can be viewed as positive compassionate outreach by a caring community. While acknowledging the benefits of this compassionate outreach to more than 25 men in the NRV, we also offer a cautionary note regarding the dilemmas of this outreach suggesting that it has the potential to mask the problems of the local housing market.
- Cost-Share Funding for EAB Treatment in Virginia's Urban ForestsStewart, Peter; Wiseman, P. Eric (Tree Care Industry Association, 2019-11-01)Urban forests often act as incubators for new populations of invasive pests and pathogens. Because major cities are global-trade and transportation hubs, non-native forest pests frequently arrive and escape to nearby trees after stowing away inside plant material or cargo crates. Additionally, the abundance of defenseless, native tree species, street-tree monocultures and stressed trees common in urban forests provides susceptible hosts for these newly arriving pests.
- Current Advances and Challenges in Fisheries and Aquaculture ScienceHallerman, Eric M.; Esteban, Maria Angeles; Baldisserotto, Bernardo (MDPI, 2022-04-08)Advances in fisheries and aquaculture science often follow the introduction of new tools or analytic methods [...]
- Deep Learning for Forest Plantation Mapping in Godavari Districts of Andhra Pradesh, IndiaMore, Snehal; Karpatne, Anuj; Wynne, Randolph H.; Thomas, Valerie A. (Virginia Tech, 2019-08)Small-area forest plantations play a vital role in the socioeconomic well-being of farmers in Southeast Asia. Most plantations are established on former agricultural land, often on land less suitable for agriculture. Plantations that are converted from natural forest have adverse impacts on biodiversity. Mapping small-area plantations is thus important to understand the dynamics of forest cover in Southeast Asia and to study the social, economic, and ecological effects of this important land cover and land use change. While the small size of forest plantations makes it difficult to detect them using moderate resolution satellite sensors, the problem is exacerbated by the high degree of mixing between plantations, surrounding vegetation, and other land covers, which often show variegated responses in satellite signals across space and time. In this paper, we study the problem of mapping small-area forest plantations in East and West Godavari districts of Andhra Pradesh, India using deep learning methods. Remotely sensed cloud-free data from the Harmonized Landsat Sentinel-2 S10 product were classified using a pixel-level neural network and training data labeled using a field-based survey in concert with expert aerial photo interpretation. We compare the performance of deep learning methods with a baseline random forest classifier in our study region of 21543 sq. km over a period of 3 years and analyze the differences in the results across land cover classes and seasons.
- Detecting Mediterranean White Sharks with Environmental DNAJenrette, Jeremy F.; Jenrette, Jennifer L.; Truelove, N. Kobun; Moro, Stefano; Dunn, Nick I.; Chapple, Taylor K.; Gallagher, Austin J.; Gambardella, Chiara; Schallert, Robert; Shea, Brendan D.; Curnick, David J.; Block, Barbara A.; Ferretti, Francesco (The Oceanography Society, 2023-01)The white shark (Carcharodon carcharias) is a globally distributed, ecologically important top predator whose biology and population dynamics are challenging to study. Basic biological parameters remain virtually unknown in the Mediterranean Sea due to its historically low population density, dwindling population size, and lack of substantial sightings. White sharks are considered Critically Endangered in the Mediterranean Sea, and recent analyses suggest that the population has declined by 52% to 96% from historical levels in different Mediterranean sectors (Moro et al., 2020). Thus, white shark sightings dating back to 1860 are being used to estimate population trajectories throughout the entire region. Though the population size is unknown, remaining individuals are thought to be primarily restricted to a handful of hotspots deemed important for their reproduction and foraging. One of these hypothesized hotspots is the Sicilian Channel, which accounts for 19% of total historical sightings.
- Editorial: Disease Ecology and BiogeographyEscobar, Luis E.; Morand, Serge (Frontiers, 2021-10-29)
- Editorial: In celebration of women in science: glycoscienceRoman, Maren; Chandran, Preethi L.; Haurat, M. Florencia (Frontiers, 2023-05)
- Effect of silvopasture system on fearfulness and leg health in fast-growing broiler chickensPaneru, Bidur; Pent, Gabriel J.; Nastasi, Shawna; Downing, Adam K.; Munsell, John F.; Fike, John H.; Jacobs, Leonie (2023-02)A silvopasture system intentionally integrates trees, forages, and livestock, allowing dual land use. These systems can provide high-quality habitat for broiler chickens; however, such systems have not been widely adopted by the broiler industry in the United States. The objective of this study was to examine the effect of silvopasture versus open pasture access on fearfulness and leg health in fast-growing broiler chickens. A total of 886 mixed-sex Ross 708 chicks in Experiment 1 (Exp 1) and 648 chicks in Experiment 2 (Exp 2) were housed in coops and had access to 16 (Exp 1) or 12 (Exp 2) 125m2 silvopasture plots (x̄ = 32% canopy cover) or open pasture plots (no canopy cover) from day 24 of age. Fearfulness was measured using a tonic immobility test (tonic immobility duration), and leg health was assessed by quantifying footpad dermatitis, hock burns, gait, and performing a latency-to-lie test on days 37-39 of age. Birds in the silvopasture treatment were less fearful than birds in the open pasture treatment. Overall, birds in both silvopasture and open pasture systems had excellent leg health. Silvopasture birds had lower footpad dermatitis scores than open pasture birds. Silvopasture birds tended to have worse gait than open pasture birds in Exp 1, but not in Exp 2. Hock burn scores and latency-to-lie did not differ between treatments in Exp 1 or Exp 2. Raising birds in silvopasture reduced fear and improved footpad health compared to birds raised in open pastures, which indicates that silvopasture systems provide some benefits for affective state and leg health in fast-growing broilers.
- Effects of a simulated fishing moratorium on the stock assessment of red porgy (Pagrus pagrus)Davis, M. L.; Berkson, James M. (National Marine Fisheries Service Scientific Publication Office, 2006-10)Much of the information available on the population status of a harvested fish species is obtained from landings data. When fishing restrictions are in place, fishery-dependent data are reduced and assessments rely more heavily on fishery-independent data. Stock assessments of red porgy (Pagrus pagrus) have shown a declining population and have led to a number of management measures, including a moratorium on fishing this species. To investigate how a lack of fishery-dependent data during a moratorium would affect stock assessment results for red porgy, we conducted simulations representing a range of periods of moratorium. As data were removed from the model, stock status indicators and projections became increasingly variable. Projections estimated that a 12-year moratorium would be needed for stock rebuilding, but simulations showed that uncertainty surrounding stock assessment estimates would increase after three years without fishery-dependent data. Unless additional data are collected during periods of strict fishing regulations, it may be difficult to accurately assess the length of time needed for the stock to rebuild and to assess the population status.
- Effects of blood extraction on horseshoe crabs (Limulus polyphemus)Walls, Elizabeth A.; Berkson, James M. (National Marine Fisheries Service Scientific Publication Office, 2003-04)Horseshoe crabs (Limulus polyphemus) are caught by commercial fishermen for use as bait in eel and whelk fisheries (Berkson and Shuster, 1999)—fisheries with an annual economic value of $13 to $17 million (Manion et al.1). Horse-shoe crabs are ecologically important, as well (Walls et al., 2002). Migratory shorebirds rely on horseshoe crab eggs for food as they journey from South American wintering grounds to Arctic breeding grounds (Clark, 1996). Horse-shoe crabs are also essential for public health (Berkson and Shuster, 1999). Biomedical companies bleed horse-shoe crabs to extract a chemical used to detect the presence of endotoxins pathogenic to humans in injectable and implantable medical devices (Novitsky, 1984; Mikkelsen, 1988). Bled horseshoe crabs are returned to the wild, subject to the possibility of postbleeding mortality. Recent concerns of overharvesting have led to conflicts among commercial fishermen, environmentalists acting on behalf of the shorebirds, and biomedical companies (Berkson and Shuster, 1999; Walls et al., 2002).
- Evaluating methods for estimating rare events with zero-heavy data: a simulation model estimating sea turtle bycatch in the pelagic longline fisheryBarlow, Paige Fithian; Berkson, James M. (National Marine Fisheries Service Scientific Publication Office, 2012-07)Estimating rare events from zero-heavy data (data with many zero values) is a common challenge in fisheries science and ecology. For example, loggerhead sea turtles (Caretta caretta) and leatherback sea turtles (Dermochelys coriacea) account for less than 1% of total catch in the U.S. Atlantic pelagic longline fishery. Nevertheless, the Southeast Fisheries Science Center (SEFSC) of the National Marine Fisheries Service (NMFS) is charged with assessing the effect of this fishery on these federally protected species. Annual estimates of loggerhead and leatherback bycatch in a fishery can affect fishery management and species conservation decisions. However, current estimates have wide confidence intervals, and their accuracy is unknown. We evaluate 3 estimation methods, each at 2 spatiotemporal scales, in simulations of 5 spatial scenarios representing incidental capture of sea turtles by the U.S. Atlantic pelagic longline fishery. The delta-lognormal method of estimating bycatch for calendar quarter and fishing area strata was the least biased estimation method in the spatial scenarios believed to be most realistic. This result supports the current estimation procedure used by the SEFSC.
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