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Publications

These publications showcase the significant science conducted in our Science Centers.

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Modeling individual effects in the Cormack-Jolly-Seber Model: A state-space formulation Modeling individual effects in the Cormack-Jolly-Seber Model: A state-space formulation

In population and evolutionary biology, there exists considerable interest in individual heterogeneity in parameters of demographic models for open populations. However, flexible and practical solutions to the development of such models have proven to be elusive. In this article, I provide a state-space formulation of open population capture-recapture models with individual effects. The...
Authors
J. Andrew Royle

Freeze-frame fruit selection by birds Freeze-frame fruit selection by birds

The choice of fruits by an avian frugivore is affected by choices it makes at multiple hierarchical levels (e.g., species of fruit, individual tree, individual fruit). Factors that influence those choices vary among levels in the hierarchy and include characteristics of the environment, the tree, and the fruit itself. Feeding experiments with wild-caught birds were conducted at El Tirol
Authors
Mercedes S. Foster

Behavior comparisons for whooping cranes raised by costumed caregivers and trained for an ultralight-led migration Behavior comparisons for whooping cranes raised by costumed caregivers and trained for an ultralight-led migration

The successful reintroduction program being run by the Whooping Crane Eastern Partnership using whooping cranes (Grus americana) trained to fly behind ultralight aircraft depends on a supply of these trained crane colts each year. The crane colts are hatched from eggs contributed by the various partners and trained to follow costume clad humans and ultralight aircraft at USGS Patuxent...
Authors
Glenn H. Olsen

Mineral resource of the month: natural and synthetic zeolites Mineral resource of the month: natural and synthetic zeolites

Volcanic rocks containing natural zeolites — hydrated aluminosilicate minerals that contain alkaline and alkaline-earth metals — have been mined worldwide for more than 1,000 years for use as cements and building stone. For centuries, people thought natural zeolites occurred only in small amounts inside cavities of volcanic rock. But in the 1950s and early 1960s, large zeolite deposits...
Authors
Robert L. Virta

Sediment dispersal in the northwestern Adriatic Sea Sediment dispersal in the northwestern Adriatic Sea

Sediment dispersal in the Adriatic Sea was evaluated using coupled three-dimensional circulation and sediment transport models, representing conditions from autumn 2002 through spring 2003. The calculations accounted for fluvial sources, resuspension by waves and currents, and suspended transport. Sediment fluxes peaked during southwestward Bora wind conditions that produced energetic...
Authors
C. K. Harris, C. R. Sherwood, R. P. Signell, A.J. Bever, J.C. Warner

Chapter 24 Lateral variability of the estuarine turbidity maximum in a tidal strait Chapter 24 Lateral variability of the estuarine turbidity maximum in a tidal strait

The behavior of the estuarine turbidity maximum (ETM) in response to freshwater flow, tidal forcing, and bed dynamics has been studied extensively by many researchers. However, the majority of investigations focus on the longitudinal position and strength of the ETM, which can vary over tidal, spring-neap, and seasonal timescales. ETMs may become longitudinally fixed due to bathymetric...
Authors
N. K. Ganju, D. H. Schoellhamer

Origin of pockmarks and chimney structures on the flanks of the Storegga Slide, offshore Norway Origin of pockmarks and chimney structures on the flanks of the Storegga Slide, offshore Norway

Seafloor pockmarks and subsurface chimney structures are common on the Norwegian continental margin north of the Storegga Slide scar. Such features are generally inferred to be associated with fluid expulsion, and imply overpressures in the subsurface. Six long gravity and piston cores taken from the interior of three pockmarks were compared with four other cores taken from the same area...
Authors
C. K. Paull, W. Ussler, W.S. Holbrook, T.M. Hill, R. Keaten, Jurgen Mienert, H. Haflidason, J.E. Johnson, W.J. Winters, T.D. Lorenson

Reevaluation of mid-Pliocene North Atlantic sea surface temperatures Reevaluation of mid-Pliocene North Atlantic sea surface temperatures

Multiproxy temperature estimation requires careful attention to biological, chemical, physical, temporal, and calibration differences of each proxy and paleothermometry method. We evaluated mid-Pliocene sea surface temperature (SST) estimates from multiple proxies at Deep Sea Drilling Project Holes 552A, 609B, 607, and 606, transecting the North Atlantic Drift. SST estimates derived from...
Authors
Marci M. Robinson, Harry J. Dowsett, Gary S. Dwyer, Kira T. Lawrence

Wildlife feeding in parks: methods for monitoring the effectiveness of educational interventions and wildlife food attraction behaviors Wildlife feeding in parks: methods for monitoring the effectiveness of educational interventions and wildlife food attraction behaviors

Opportunities to view and interact with wildlife are often an important part of high quality recreational experiences. Such interactions frequently include wildlife feeding, resulting in food-conditioned behaviors that may cause harm to both wildlife and visitors. This study developed and applied efficient protocols for simultaneously evaluating wildlife feeding-related behaviors of...
Authors
Jeffrey L. Marion, Robert G. Dvorak, Robert E. Manning

Estimating species occurrence, abundance, and detection probability using zero-inflated distributions Estimating species occurrence, abundance, and detection probability using zero-inflated distributions

Researchers have developed methods to account for imperfect detection of species with either occupancy (presence-absence) or count data using replicated sampling. We show how these approaches can be combined to simultaneously estimate occurrence, abundance, and detection probability by specifying a zero-inflated distribution for abundance. This approach may be particularly appropriate...
Authors
S.J. Wenger, Mary C. Freeman
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