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Explore WARC's science publications.

Filter Total Items: 3350

A deep reef in deep trouble

The well-documented degradation of shallower reefs which are often closer to land and more vulnerable to pollution, sewage and other human-related stressors has led to the suggestion that deeper, more remote offshore reefs could possibly serve as sources of coral and fish larvae to replenish the shallower reefs. Yet, the distribution, status, and ecological roles of deep (>30 m) Caribbean reefs ar
Authors
Charles Menza, M. Kendall, C. Rogers, J. Miller

Environmental and plant community determinants of species loss following nitrogen enrichment

Global energy use and food production have increased nitrogen inputs to ecosystems worldwide, impacting plant community diversity, composition, and function. Previous studies show considerable variation across terrestrial herbaceous ecosystems in the magnitude of species loss following nitrogen (N) enrichment. What controls this variation remains unknown. We present results from 23 N-addition expe
Authors
C.M. Clark, E.E. Cleland, S.L. Collins, J.E. Fargione, L. Gough, K.L. Gross, S.C. Pennings, K.N. Suding, J.B. Grace

Large-scale causes of variation in the serpentine vegetation of California

Serpentine vegetation in California ranges from forest to shrubland and grassland, harbors many rare and endemic species, and is only moderately altered by invasive exotic species at the present time. To better understand the factors regulating the distribution of common/representative species, endemic/rare species, and the threat of exotics in this important flora, we analyzed broad-scale communi
Authors
J.B. Grace, H.D. Safford, S. Harrison

Habitat relationships of birds overwintering in a managed coastal prairie

Grassland birds are considered to be rapidly declining in North America. Management approaches for grassland birds frequently rely on prescribed burning to maintain habitat in suitable condition. We evaluated the relationships among years since burn, vegetation structure, and overwintering grassland bird abundance in coastal prairie. Le Conte's Sparrows (Ammodramus leconteii) were most common in a
Authors
H.Q. Baldwin, J.B. Grace, W.C. Barrow, F.C. Rohwer

Species richness and soil properties in Pinus ponderosa forests: A structural equation modeling analysis

Question: How are the effects of mineral soil properties on understory plant species richness propagated through a network of processes involving the forest overstory, soil organic matter, soil nitrogen, and understory plant abundance? Location: North-central Arizona, USA. Methods: We sampled 75 0.05-ha plots across a broad soil gradient in a Pinus ponderosa (ponderosa pine) forest ecosystem. We e
Authors
D.C. Laughlin, S.R. Abella, W.W. Covington, J.B. Grace

Population estimates of Hyla cinerea (Schneider) (Green Tree frog) in an urban environment

Hyla cinerea (Green Treefrog) is a common wetlands species in the southeastern US. To better understand its population dynamics, we followed a relatively isolated population of Green Treefrogs from June 2004 through October 2004 at a federal office complex in Lafayette, LA. Weekly, Green Treefrogs were caught, measured, marked with VIE tags, and released. The data were used to estimate population
Authors
L. Pham, S. Boudreaux, S. Karhbet, B. Price, A. S. Ackleh, J. Carter, N. Pal

Three new percid fishes (Percidae: Percina) from the Mobile Basin drainage of Alabama, Georgia, and Tennessee

Three new species of Percina are described from upland drainages of the Mobile Basin. Two of the three species are narrowly distributed: P. kusha, the Bridled Darter, is currently known only from the Conasauga River drainage in Georgia and Tennessee and Etowah River drainage in Georgia, both tributaries of the Coosa River, and P. sipsi, the Bankhead Darter, which is restricted to tributaries of Si
Authors
J.D. Williams, D.A. Neely, S. J. Walsh, N.M. Burkhead

Molecular systematics of Serrasalmidae: Deciphering the identities of piranha species and unraveling their evolutionary histories

Piranhas and their relatives have proven to be a challenging group from a systematic perspective, with difficulties in identification of species, linking of juveniles to adults, diagnosis of genera, and recognition of higher-level clades. In this study we add new molecular data consisting of three mitochondrial regions for museum vouchered and photo-documented representatives of the Serrasalmidae.
Authors
B. Freeman, L.G. Nico, M. Osentoski, H.L. Jelks, T.M. Collins

Changes in a northwestern Florida gulf coast herpetofaunal community over a 28-y period

Population declines of amphibians and reptiles throughout the world have led to the initiation of projects to monitor their status and trends. Historical collections give an indication of which species occurred in an area at one time, although the ambiguity surrounding locations and environmental conditions associated with collection decreases the value of this information source. Resampling using
Authors
C. K. Dodd, W.J. Barichivich, S. A. Johnson, J.S. Staiger

Nutrient addition differentially affects ecological processes of Avicennia germinans in nitrogen versus phosphorus limited mangrove ecosystems

Nutrient over-enrichment is a major threat to marine environments, but system-specific attributes of coastal ecosystems may result in differences in their sensitivity and susceptibility to eutrophication. We used fertilization experiments in nitrogen (N)- and phosphorus (P)-limited mangrove forests to test the hypothesis that alleviating different kinds of nutrient limitation may have different ef
Authors
Ilka C. Feller, C. E. Lovelock, K.L. McKee

Deep-water chaunacid and lophiid anglerfishes (Pisces: Lophiiformes) off the south-eastern United States

Recent research cruises to deep (80-910 m) reef habitats off the south-eastern U.S. and in the northern Gulf of Mexico have provided new information on the diagnostic characteristics, behaviours, colour patterns in life, bottom associations, distributions and maximum sizes of species of the anglerfish genera Chaunax, Lophiodes and Sladenia. Chaunax stigmaeus occurred much further south than previo
Authors
John H. Caruso, Steve W. Ross, K. J. Sulak, G.R. Sedberry