Nacote Creek Research Station

Port Republic, NJ, United States

Nacote Creek Research Station

Port Republic, NJ, United States
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Garrison L.P.,National Oceanic and Atmospheric Administration | Link J.S.,National Oceanic and Atmospheric Administration | Kilduff D.P.,University of California at Davis | Cieri M.D.,West Marine | And 5 more authors.
ICES Journal of Marine Science | Year: 2010

Ecosystem-based fisheries management requires tools to place fish-stock dynamics in the broader context of fishery, predator, and competitive removals. Multispecies virtual population analysis (MSVPA) is an approach to quantifying predator-prey interactions and estimating the rates of predation mortality for exploited fish populations. Here, an extended MSVPA (MSVPA-X) is presented as an alternative to existing MSVPA approaches. Notably, MSVPA-X uses index-tuned VPA methods, applies a more flexible feeding model, and includes an alternative functional feeding response. The MSVPA-X model is applied to a western Atlantic fish community, focusing on Atlantic menhaden and its major fish predators, and a sensitivity analysis of major model parameters is presented. The sensitivity analysis highlights the need for adequate diet sampling. The MSVPA-X represents an improvement over previous approaches by increasing the flexibility to model seasonal and interannual dynamics in the strength of predator-prey interactions. Model results demonstrate that, for menhaden in particular, and forage fish in general, quantifying predation mortality is an important part of effective assessments of forage fish, their predators, and the fisheries of both. © 2009 International Council for the Exploration of the Sea. Published by Oxford Journals. All rights reserved.

Coluccy J.M.,Ducks Unlimited Inc. | Castelli M.V.,117 North Cologne Avenue | Castelli M.V.,Lafayette College | Castelli P.M.,Nacote Creek Research Station | And 4 more authors.
Journal of Wildlife Management | Year: 2015

Understanding the true metabolizable energy (TME) of foods is critical to estimating the energetic carrying capacity of landscapes for migrating and wintering waterfowl. We estimated gross energy, nutrient composition, and TMEN (TME corrected for zero nitrogen balance) for 7 foods that are commonly found in the diet of American black duck (Anas rubripes) and other waterfowl wintering along the Atlantic Coast. TMEN values (x-±SE) were 3.66±0.12kcal/g for mummichog (Fundulus heteroclitus), 2.02±0.12kcal/g for grass shrimp (Palaemonetes intermedius, P. pugio, and P. vulgaris), 1.57±0.11kcal/g for fiddler crabs (Uca minax, U. pugilator, and U. pugnax), 1.42±0.13kcal/g for sea lettuce (Ulva lactuca), 1.39±0.12kcal/g for saltmarsh cordgrass seeds (Spartina alterniflora), 1.10±0.14kcal/g for widgeon grass vegetation (Ruppia maritima), and 0.77±0.16kcal/g for saltmarsh snails (Melampus bidentatus). TMEN estimated for foods in this study will assist conservation planners in carrying out bioenergetics modeling along the Atlantic Coast. © 2014 The Wildlife Society.

Goldstein M.,University of Delaware | Williams C.K.,University of Delaware | Castelli P.M.,Nacote Creek Research Station | Castelli P.M.,U.S. Fish and Wildlife Service | Duren K.R.,University of Delaware
Wildlife Society Bulletin | Year: 2016

Habitat limitation and availability of food energy may be the cause of decline in American black duck (Anas rubripes) populations. Estimating food availability is a critical step in developing winter carrying-capacity estimates for black ducks. Recent research has estimated the biomass and energy supply of winter black duck foods in coastal marshes using a single-core sampling method, but estimates had large variability. We tested whether taking bulk core samples (i.e., homogenizing multiple core samples and subsampling a single core from it) at the same location (vs. a single core sample) would alter the mean and variance in food estimates in 7 different landscape–vegetation types (hereafter, habitat types: mudflat, subtidal, low marsh, high marsh, quasi-tidal pools, a tidal impoundment, and a freshwater impoundment) in coastal New Jersey, USA, during 2011. In all but one habitat type, there were no differences in the mean biomass or the mean energy density estimates for the single core samples and the bulk core samples, across all food types. Variance was reduced in subtidal and quasi-tidal pool habitats, but variance increased in tidal impoundments. Assessing time and cost-efficiency of bulk samples over single samples, cost per sample increased 4–12%/core. Because we observed little difference in food biomass, energy, and their respective variance estimates between single and bulk methods, while recording a slightly greater cost, we recommend researchers use the single-core sampling method to save both time and money. Further reductions in variance will likely need to be achieved through increased sample sizes. © 2016 The Wildlife Society. © The Wildlife Society, 2016

Guerena K.B.,University of Delaware | Castelli P.M.,Nacote Creek Research Station | Nichols T.C.,201 County Route 631 | Williams C.K.,University of Delaware
Wildlife Society Bulletin | Year: 2012

Disruption associated with nest visits during the hatch period of waterfowl can cause partial abandonment of hatchlings, potentially causing bias in the survival of marked birds. We evaluated the use of a mesh clutch-containment bag to capture and mark entire broods of 151 resident Canada goose (Branta canadensis) nests, prior to hatch, while minimizing observer-caused disruption during brooding. The study was conducted in New Jersey, USA, from April to June 2010. No differences were found in hatch success or the number of hatchlings marked between contained clutches and the control group. Although this technique was not beneficial in studying gosling survival in temperate nesting populations, it may be effective in subArctic nesting conditions where nest visits are conducted using a more invasive approach such as a helicopter. © 2012 The Wildlife Society.

Cramer D.M.,University of Delaware | Castelli P.M.,Nacote Creek Research Station | Yerkes T.,Ducks Unlimited Inc. | Williams C.K.,University of Delaware
Journal of Wildlife Management | Year: 2012

Midwinter waterfowl survey data indicates a long-term decline in the number of wintering American black ducks (Anas rubripes), potentially due to habitat limitations. In order for future estimates of carrying capacity to be determined, it is critical that regional food availability is estimated. We collected pairs of habitat core samples (n = 510) from 5 habitat types in southern New Jersey, USA, during October, January, and April 2006-2008 to estimate resource availability and variability. We collected upper gastrointestinal tracts from hunter-killed birds (n = 45) and late season collections (n = 19) to identify food items and limited our estimates of resource availability to only winter food items; thereby reducing the availability of seed foods found in our core samples by 38% and animal foods by 96%. We did not detect differences in years or sampling period, but did between habitat types. Mudflat habitat had the greatest availability of invertebrate and vertebrate food items and appeared to supply the bulk of energy to black ducks wintering in southern New Jersey. We suggest conservation efforts to be focused on restoring or enhancing mudflat habitat as an integral component of an ecologically functioning salt marsh to increase food availability. © 2011 The Wildlife Society. Copyright © The Wildlife Society, 2011.

Ladin Z.S.,University of Delaware | Castelli P.M.,Nacote Creek Research Station | Mcwilliams S.R.,University of Rhode Island | Williams C.K.,University of Delaware
Journal of Wildlife Management | Year: 2011

We conducted extensive behavioral and food sampling of Atlantic brant (Branta bernicla hrota) across their winter range and used time-activity budgets for brant to determine daily energy expenditure (DEE). Sampling occurred 1 December-31 May 2006-2008 in 11,225-km2 sites between Rhode Island and Virginia containing important estuarine and upland habitat. To calculate DEE we used instantaneous scan sampling to estimate time-activity budgets. We also determined foods eaten by brant and energy density of food plants. Last, we quantified body condition of brant, which differed among years, months, regions, and ages, and sexes. Overall DEE for brant was 1,530 ± 64 kJ/day. There was considerable variation in time-activity budgets among years, months, regions, habitat, tide, temperature, and time-of-day, but we detected no significant difference in DEE of brant between years or among regions. However, DEE in January (2,018 ± 173 kJ/day) was nearly double the DEE of brant in May (1,048 ± 137 kJ/day). Brant spent their time feeding (32.3%), swimming (26.2%), resting (16.2%), and flying (14.5%). The percent of brant foreguts sampled contained macroalgae (53%) eelgrass (Zostera marina; 18%), salt marsh cordgrass (Spartina alterniflora; 17%), and terrestrial grass (Poa. sp.) and clover (Trifollium sp.; 9%). Energy density differed by vegetation type: macroalgae (12.6 ± 0.1 kJ/g), eelgrass (14.1 ± 0.1 kJ/g), new-growth salt marsh cordgrass (16.9 ± 0.2 kJ/g), and terrestrial grass and clover (17.7 ± 0.1 kJ/g). Atlantic brant exhibited behavioral plasticity thereby allowing modification of daily activity budgets to meet seasonally varying energetic requirements associated with wintering and spring staging. Recognizing a variable DEE can be used along with eventual estimates of food biomass and total metabolizable energy on the landscape to calculate carrying capacity (goose use days) on state, region, or range-wide scales. © 2011 The Wildlife Society.

Able K.W.,Rutgers University | Grothues T.M.,Rutgers University | Turnure J.T.,Rutgers University | Byrne D.M.,Nacote Creek Research Station | Clerkin P.,Rutgers University
Fishery Bulletin | Year: 2012

Distribution, movements, and habitat use of small (<46 cm, juveniles and individuals of unknown maturity) striped bass (Morone saxatilis) were investigated with multiple techniques and at multiple spatial scales (surveys and tag-recapture in the estuary and ocean, and telemetry in the estuary) over multiple years to determine the frequency and duration of use of non-natal estuaries. These unique comparisons suggest, at least in New Jersey, that smaller individuals (<20 cm) may disperse from natal estuaries and arrive in non-natal estuaries early in life and take up residence for several years. During this period of estuarine residence, individuals spend all seasons primarily in the low salinity portions of the estuary. At larger sizes, they then leave these non-natal estuaries to begin coastal migrations with those individuals from nurseries in natal estuaries. These composite observations of frequency and duration of habitat use indicate that non-natal estuaries may provide important habitat for a portion of the striped bass population.

Ashton-Alcox K.A.,Rutgers University | Powell E.N.,University of Southern Mississippi | Hearon J.A.,Delaware Bay Office | Tomlin C.S.,Delaware Bay Office | Babb R.M.,Nacote Creek Research Station
Journal of Shellfish Research | Year: 2013

New Jersey manages a quota-based fishery on its Delaware Bay oyster beds. A transplant program conducted each year to augment the quota moves a small proportion of oysters from upbay beds to downbay beds where the oysters quickly improve in market quality. High mortality rates downbay warrant minimizing the number of small oysters moved downbay and retaining recruitment potential warrants limiting the quantity of cultch moved downbay. Consequently, automatic cullers are used and each transplant is monitored. An observer study was conducted during the 2011 transplant to evaluate the method of transplant monitoring. Samples taken throughout the day were compared with samples taken at the end of the day to determine if end-of-day sampling was sufficient to characterize the entire deckload. No significant difference was found between samples taken periodically during the day and end-of-day samples in 7 of 9 observed deckloads. No significant differences were found between 3 end-of-day samples taken to characterize the deckload and a larger sampling intensity of 12; thus, the current sampling intensity of 3 end-of-day samples to describe the deckload is sufficient. Because of varying gear configurations and economic incentives to load the deck quickly, we also compared cultch fractions and oyster size frequencies among boats. Representative distributions from different boats, days, and beds in the observer data set suggest that boats differing by 6-7% in cultch fraction should be identified routinely as significantly different from other boats. Significant differences were observed in oyster size frequency among boat deckloads more often than in cultch fraction. Further study is needed to determine the extent to which gear configuration affects deckload composition.

Wuenschel M.J.,Rutgers University | Able K.W.,Rutgers University | Vasslides J.M.,Rutgers University | Byrne D.M.,Nacote Creek Research Station
Fishery Bulletin | Year: 2013

Piscivorous fishes, many of which are economically valuable, play an important role in marine ecosystems and have the potential to affect fish and invertebrate populations at lower trophic levels. Therefore, a quantitative understanding of the foraging ecology of piscivores is needed for ecosystem-based fishery management plans to be successful. Abundance and stomach contents of seasonally co-occurring piscivores were examined to determine overlap in resource use for Summer Flounder (Paralichthys dentatus; 206-670 mm total length [TL]), Weakfish (Cynoscion regalis; 80-565 mm TL), Bluefish (Pomatomus saltatrix; 55-732 mm fork length [FL]), and Striped Bass (Morone saxatilis; 422- 920 mm FL). We collected samples from monthly, fishery-independent trawl surveys conducted on the inner continental shelf (5-27 m) off New Jersey from June to October 2005. Fish abundances and overlaps in diet and habitat varied over this study period. A wide range of fish and invertebrate prey was consumed by each species. Diet composition (determined from 1997 stomachs with identifiable contents) varied with ontogeny (size) and indicated limited overlap between most of the species size classes examined. Although many prey categories were shared by the piscivores examined, different temporal and spatial patterns in habitat use seemed to alleviate potential competition for prey. Nevertheless, the degree of overlap in both fish distributions and diets increased severalfold in the fall as species left estuaries and migrated across and along the study area. Therefore, the transitional period of fall migration, when fish densities are higher than at other times of the year, may be critical for unraveling resource overlap for these seasonally migrant predators.

Jones O.E.,University of Delaware | Williams C.K.,University of Delaware | Castelli P.M.,Nacote Creek Research Station | Castelli P.M.,U.S. Fish and Wildlife Service
Waterbirds | Year: 2014

Previous efforts to estimate the daily energy expenditure of American Black Ducks (Anas rubripes) have relied upon diurnal behavior observations or predictive allometric equations. American Black Duck behavior was quantified during morning crepuscular, diurnal, evening crepuscular and nocturnal periods to create a 24-hr time-energy budget. Behaviors and energy expenditure differed between periods and months, with hourly energy expenditure highest during the morning crepuscular period and lowest during the nocturnal period. Daily energy expenditure estimates based on a 24-hr time-energy budget were lower than estimates calculated from extrapolated diurnal behavioral data as well as a predictive allometric equation that uses a generalized dabbling duck resting metabolic rate. However, there was no difference between the 24-hr time budget and a predictive allometric equation using American Black Duck specific resting metabolic rates. Future researchers and managers should acknowledge the assumptions of each methodology to estimate daily energy expenditure when using a bioenergetic approach to estimate carrying capacity. © 2014, Waterbirds Society. All rights reserved.

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