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Vernal pools are isolated ephemeral bodies of water that are often overlooked on the landscape. Despite their temporary nature, these pools are important to forest communities, providing critical breeding habitat for amphibians and an important food and water source for other taxonomic groups including birds, bats, and other terrestrial vertebrates. Sparse information about vernal pools in the upper Midwest, including Pictured Rocks National Lakeshore (PIRO), inhibits conservation. We sampled soil, vegetation, and amphibians in 21 vernal pools in PIRO during spring 2010 to provide quantitative and qualitative evaluation of vernal pool abiotic and biotic characteristics within PIRO to help managers determine which pools to prioritize for conservation. Average vernal pool size sampled was 0.124 ha. Soils had an average of 13.5% carbon and 0.7% nitrogen. Vegetation was diverse within the vernal pools, with 115 vascular plants identified. Five species of amphibians were encountered during our surveys. We created a vernal pool classification system based on: (1) pool depression characteristics (one depression versus many interconnected depressions and whether canopy was open or closed) and (2) vegetation community type. This resulted in five vernal pool types: three herbaceous communities with open canopies and defined circular/elliptical boundaries (classic pools) and two forested closed canopy communities with irregular perimeters and interconnected mini-basins (complex pools). The two forested communities had the highest vegetation species richness, due mostly to greater number of microsites (downed logs, hummocks, etc.) for vegetation. Hydroperiod index and soil carbon were found to correspond to the vegetation classes. Amphibian species richness was highest in the classic pools and the majority of the amphibians encountered were in the sedge community type. This classification system, potentially effective for vernal pools throughout glaciated northeastern North America, will help managers prioritize vernal pools for conservation., INTRODUCTION Woodland vernal pools are geographically isolated, seasonally flooded bodies of water that are surrounded by forested uplands (Tiner, 2003). Though these pools are relatively small in terms of the [...]

The fertility announcement hypothesis proposes that avian males should sing at a high rate when their mate is fertile to guard their paternity. We examined if male Song Sparrows (Melospiza melodia) sing more during the incubation period when they are free of constraints of physical mate guarding. We assessed song rates of eight males for 1 hr-periods every 1-2 days during each breeding stage over two consecutive broods within one season. Males sang significantly more during periods when their mate was incubating than during the pre-fertile, or fertile periods, or while feeding young (second brood). Males may be singing at high rates during incubation to maintain contact with their mate and/or to advertise for extra-pair copulations., Song has two main functions, territory defense and mate attraction (Catchpole and Slater 1995). Song rate typically decreases after pairing (Catchpole and Slater 1995), but males of many species continue [...]

Studies of song and its function in suboscine passerines are rare. We examined spatial and temporal variation in song structure in a wild population of Olive-sided Flycatchers (Contopus cooperi) and tested among hypotheses explaining this variation. Repeatable variation in song type was observed both within and among individuals. More than 10% of territorial males expressed atypical song types, i.e., permutations of sequential missing and repeated elements of the typical adult song. Atypical songs were predominantly expressed by unpaired males independent of habitat type. A small fraction of males sang atypical song through the middle of the breeding season, but all males sang only stereotypical adult song by the end of the season. These results suggest the expression of atypical songs reflect protracted vocal development rather than evolution of new song types, geographic variation in song structure, or an extensive song repertoire in Olive-sided Flycatchers., Suboscines comprise ~20% (1,151 species) of the Order Passeriformes (Sibley and Monroe 1990), but studies of bird song and its functions have focused almost exclusively on oscines. Suboscines are characteristically [...]

We found nine nests of the Grey-hooded Parrotbill (Paradoxornis zappeyi) during April through July 2003 at Wawushan Natural Reserve, Sichuan, southwestern China. This report is the first description of the nest sites, nests, eggs, and breeding behavior of this parrothill, and the first documentation of nestling growth from hatching until fledging. The nests were constructed mainly of bamboo (Bashania faberi) leaves, fibrous roots, and moss by both male and female. Nests were bowl shaped and in bamboo thickets 81-122 cm above ground, and 17-68 cm below the top of bamboo leaves. Clutch size was 3.1 eggs (n = 8 nests) and eggs were oval, pale blue in color with a mean mass of 1.3 g. Incubation and provisioning of nestlings were by both parents. The nestling period was 13-14 days with a hatching rate of 0.52 and mean reproductive success rate of 0.48 fledglings per nest., The Grey-hooded Parrotbill (Paradoxornis zappeyi) is a rare Chinese endemic, one of five threatened members of a 10-species avian suite entirely restricted to the Central Sichuan Mountains Endemic Bird Area [...]

We studied breeding biology, parental roles, and social mating system of the Bay-capped Wren-Spinetail (Spartonoica maluroides), a habitat specialist furnariid, in the Argentinean pampas. We found 42 nests during 2004-2007, two during egg laying, 28 during incubation, and 12 with nestlings. Mean clutch size was 3.17 eggs (n = 29), the incubation period was 13 days, and nestlings remained in the nest for 12 days before fledgling. Bay-capped Wren-Spinetails are socially monogamous; both males and females develop a brood patch and contribute to incubation, brooding, and provisioning of nestlings. Wren-Spinetails are unique among furnariids as they build an open cup nest with a few presenting a loose domed roof. Breeding success of Bay-capped Wren-Spinetails was higher (total probability of nesting success = 0.508) than other species of sympatric passerines because of low nest predation and high nest survival rates during incubation and nestling rearing stages., The members of the Furnariidae (236 described species) inhabit a great diversity of biomes in the Neotropics, including lowland and montane forests, grasslands, salt and fresh water marshes, and rocky [...]

We studied the breeding biology of Purple Swamphens (Porphyrio porphyrio poliocephalus) at Nainar Pond in Tirunelveli, South India from January 2003 to May 2004. Peak breeding activity occurred from the second week of January to the first week of March. Nests were built on thick floating vegetation closest to the bank of the pond. Nesting material consisted of whole plants, stems, and leaves of Eichhornia crassipes, Jussieua repens, Pistia stratiotes, Ipomoea aquatica, and Cyperus rotundus with E. crassipes being most preferred. Nest dimensions were variable. Clutch size varied from three to seven eggs with a mean ([+ or -] SD) clutch size of 4.5 [+ or -] 1.5 and a model clutch size of four eggs. Mean volume of all eggs was 32.3 [+ or -] 3.5 [cm.sup.3]. The length of the incubation period was estimated as 19.8 [+ or -] 1.2 days. Nest and egg hatching success were estimated as 80.0% and 61.1%, respectively, while overall fledging success was 42.0%., The Purple Swamphen (Porphyrio porphyrio) is a medium sized water bird (Ali 1981) which lives in marshes, lagoons, and reservoirs with appropriate vegetation cover and water depth. Undisturbed areas with [...]

We provide the first description of the nest, eggs, and nestlings of the Planalto Woodcreeper (Dendrocolaptes platyrostris), a secondary cavity-nester, based on three nests in natural cavities and 14 in nest boxes. Nests were found from October to January in 1997, 2006, and 2007 in the humid Chaco and Atlantic Forest of Argentina. Planalto Woodcreepers used natural cavities and nest boxes 40-60 cm deep with entrance diameters of 5-12 cm. They selected the deepest nest boxes available. Three or four white eggs were laid on a bed of bark flakes and incubated for 14-16 days. Newly hatched nestlings had pink skin with gray down, yellow mouth linings, and large whitish gape flanges. They opened their eyes when 6-7 days of age and fledged at 16-18 days. Nearly all nestlings were infested with botflies (Philornis sp.). Both adults contributed to nest building, incubation, nestling-rearing, and nest sanitation., The woodcreepers are a group of cavity-nesting neotropical birds now recognized by many authors as members of the Furnariidae (Irestedt et al. 2002, 2006; Fjeldsa et al. 2005). They are [...]

The Northern Harrier (Circus cyaneus) is of major conservation and management concern in the northeastern United States. We studied habitat use of foraging adult male and female harriers on Nantucket Island, Massachusetts among four habitat types: grassland, shrubland, mowed, and burned. Overall, foraging indices were not correlated to nest proximity and harriers foraged significantly less frequently in mowed habitat than in the other habitat types. Management of harrier habitat in the northeastern United States may not exclusively require grasslands, and mowing reduces foraging habitat., Northern Harriers (Circus cyaneus) have been identified as a species of national concern by the U.S. Fish and Wildlife Service (USDI 2002), and populations have declined dramatically along the east [...]

We studied adult Peruvian Boobies (Sula variegata) on two islands in northern Peru to classify males and females using DNA-based techniques. We used this information to (1) assess the extent of size dimorphism in this species, (2) identify males and females using discriminant functions of external characters, and (3) validate use of voice as a reliable method for identifying male and female Peruvian Boobies in the field. Female Peruvian Boobies were 19% heavier and their culmens and wings were 3 and 4% larger than males, respectively. A discriminant function that included body weight and wing chord correctly classified 90% of the birds. Alternatively, 88% of correct identification of males and females was obtained with a function that incorporated only wing chord. Whistles were performed exclusively by males (25/25 of cases), whereas grunts or goose-like honk vocalizations were performed only by females (24/24 of cases). The female-larger size dimorphism of Peruvian Boobies is intermediate in comparison to other Sula boobies. Calls and biometry provide a fast, reliable, and inexpensive method for classifying most adult Peruvian Boobies as males or females in the field. We recommend a hierarchical system for classification of male and female Peruvian Boobies: (1) use of vocalizations, (2) use of body weight and wing chord when the bird did not vocalize and was weighed immediately after daybreak or before the first feeding trip of the day, and (3) use of wing chord only when there is uncertainty in temporal variations of body weight., Most seabird species do not display male/ female-specific differences in coloration of external features such as plumage, feet, or secondary ornaments (Harrison 1983, Redman et al. 2002, Gaston 2004, Ropert-Coudert [...]

ABSTRACT.--Blackwater National Wildlife Refuge on the Delmarva Peninsula, Maryland, USA has been the wintering area of a small population of Lesser Snow Geese (Chen caerulescens caerulescens; LSGO) since the 1930s. Snow Geese primarily pair in wintering areas and gene flow could be restricted between this and other LSGO wintering populations. Winter pair formation also could facilitate interbreeding with sympatric but morphologically differentiated Greater Snow Geese (C. c. atlantica; GSGO).We sequenced 658 bp of the mitochondrial DNA control region for 68 Snow Geese from East Coast and Louisiana wintering populations to examine the level of genetic differentiation among populations and subspecies. We found no evidence for genetic differentiation between LSGO populations but, consistent with morphological differences, LSGO and GSGO were significantly differentiated. We also found a lack of genetic differentiation between different LSGO morphotypes from Louisiana. We examined available banding data and found the breeding range of Delmarva LSGO overlaps extensively with LSGO that winter in Louisiana, and documented movements between wintering populations. Our results suggest the Delmarva population of LSGO is not a unique population unit apart from Mid-Continent Snow Geese., A small population of Lesser Snow Geese (Chen caerulescens caerulescens; LSGO) has been wintering on the Delmarva Peninsula on the east coast of the United States, mostly at Blackwater National [...]

Songs of individual male Blue Grosbeaks (Passerina caerulea) typically begin with the same combination of elements, but the sequence and number of elements in the latter portion of songs vary. We examined the possible functions of within-song variation in Blue Grosbeaks at the Blue Grass Army Depot near Richmond, Kentucky, USA from 15 April to 31 July 2007. We examined singing rates and song characteristics of second-year (SY; n = 6) and after-second-year (ASY; n = 14) males, and conducted playback experiments (n = 15) to identify the possible function of variation in song length. Male Blue Grosbeaks sang at highest rates prior to pairing, maintained relatively high singing rates during the post-pairing/pre-nesting and nest-building/egg-laying stages, and sang at lower rates during the incubation, nestling, and fledgling stages. These results suggest high singing rates are important in attracting mates and establishing territories, and lower singing rates may result from trade-offs associated with parental care. Males used longer songs during aggressive encounters with conspecifics and responded more aggressively to playback of longer songs. This suggests songs containing more elements signal increased aggression. Within-song variation may be an important way to vary song meaning for male Blue Grosbeaks, and perhaps other males in species with a single song type but repertoires of several different song elements., Singing by male songbirds serves a variety of functions, ranging from establishing territories and attracting mates (Smith 1991) to distracting predators (Ritchison 1991), communicating with young (Beecher 1990), coordinating nest [...]

We examined the complex of populations of the Loggerhead Kingbird (Tyrannus caudifasciatus), a West Indian endemic. We separate populations in Puerto Rico and Isla Vieques (T. taylori), and Hispaniola (T. gabbii) as distinct species. Subspecific distinction is assigned to populations in Cuba, Isla de Pinos, and Cuban satellites (T. caudifasciatus caudifasciatus); Cayman Islands (T. c. caymanensis); Jamaica (T. c. jamaicensis); and the Bahamas (T. c. bahamensis) on the basis of differences in plumage coloration and pattern, size, vocalizations, and distribution., The Loggerhead Kingbird (Tyrannus caudifasciatus) is endemic to the Bahama Islands and Greater Antilles, although occasionally stragglers have been reported in southern Florida (Bond 1978:3, Robertson and Woolfenden 1992, AOU [...]

Scoter vocalizations may have a role in pair formation and pair bonding. I compared the courtship calls of male Black Scorers (Melanitta nigra nigra and M. n. americana) using published and archived recordings. Courtship calls of the two subspecies differed diagnosably in duration. In contrast, recordings from different localities within the ranges of each taxon showed no diagnosable differentiation. This finding represents the first indication these taxa differ in characters other than bill morphology and supports recent proposals to treat M. n. americana as a distinct species (M. americana). Vocal displays, in contrast to courtship displays, of anatids have not been used for assessment of species limits in Anatidae. My results indicate vocalizations are a potentially useful additional character in species-level taxonomy of anatids., Courtship displays of anatids have attracted substantial attention from behavioral scientists (e.g., Heinroth 1911, Lorenz 1951-1953, Johnsgard 1965), and interspecific variation has been analysed and interpreted in an evolutionary context [...]

Northern Bobwhite (Colinus virginianus) populations have been declining throughout their range, but some of the sharpest declines have been documented in the Mid-Atlantic states. We conducted a 2 year (2006-2007) breeding season (1 May-30 Sep) telemetry study in southern New Jersey to collect baseline data on Northern Bobwhite reproductive rates, and nest and brood microhabitat selection. We located 23 Northern Bobwhite nests, of which 21 were usable for survival analyses. Incubation-period nest survival rate was 0.454 [+ or -] 0.010 (95% CI = 0.280-0.727). Mean clutch size was 14.2 [+ or -] 0.58 (range 10-19, n = 20) and hatching success was 96.1 [+ or -] 2.0% (range 86-100%, n = 10). The estimated probability that an individual that entered the breeding season would initiate incubation of [greater than or equal to] 1 nest was 0.687 for females and 0.202 for males. Nest microhabitat selection was positively related to visual obstruction and percentage of litter. Brood microhabitat selection was positively related to visual obstruction, vegetation height, and percentage of forbs but negatively related to percentage of cool season grass and litter. Fecundity metrics for Northern Bobwhites in southern New Jersey appear similar to those reported elsewhere in the species' range. Conservation efforts to increase Northern Bobwhite reproductive success in southern New Jersey should focus on increasing the quantity of available breeding habitat., Northern Bobwhite (Colinus virginianus) populations have been declining throughout most of their range (Sauer et al. 2008). Some of the most marked declines in Northern Bobwhite populations are occurring at [...]

Since Hsp90 is a known modulator of HSF1 activity, we examined the effects of two pharmacological inhibitors of Hsp90, novobiocin and geldanamycin, on HSF1 DNA-binding activity in the Xenopus oocyte model system. Novobiocin exhibits antiproliferative activity in culture cells and interacts with a C-terminal ATP-binding pocket on Hsp90, inhibiting Hsp90 autophosphorylation. Treatment of oocytes with novobiocin followed by heat shock results in a dose-dependent decrease in HSF1 DNA-binding and transcriptional activity. Immunoprecipitation experiments demonstrate novobiocin does not alter HSF1 activity through dissociation of Hsp90 from either monomeric or trimerized HSF1, suggesting that the effect of novobiocin on HSF1 is mediated through alterations in Hsp90 autophosphorylation. Geldanamycin binds the N-terminal ATPase site of Hsp90 and inhibits chaperone activity. Geldanamycin treatment of oocytes resulted in a dosedependant increase in stability of active HSF1 trimers during submaximal heat shock and a delay in disassembly of trimers during recovery. The results suggest that Hsp90 chaperone activity is required for disassembly of HSF1 trimers. The data obtained with novobiocin suggests the C-terminal ATP-binding activity of Hsp90 is required for the initial steps of HSF1 trimerization, whereas the effects of geldanamycin suggest N-terminal ATPase and chaperone activities are required for disassembly of activated trimers. These data provide important insight into the molecular mechanisms by which pharmacological inhibitors of Hsp90 affect the heat shock response. Key words: HSF1, Hsp90, Xenopus, novobiocin, geldanamycin. Puisque la Hsp90 est un modulateur connu de l'activite de HSF1, nous avons examine les effets de deux de ses inhibiteurs pharmacologiques, la novobiocine et la geldanamycine, sur l'activite de liaison a l'ADN de HSF1 dans un mode le d'ovocytes de Xenopus. La novobiocine inhibe la proliferation des cellules en culture et interagit avec la poche de liaison de l'ATP de la Hsp90, inhibant ainsi son autophosphorylation. Un traitement des ovocytes a la novobiocine suivi d'un choc thermique resulte en une diminution de la liaison a l'ADN et de l'activite transcriptionnelle de HSF1 et ce, de facon dependante de la concentration. Des experiences d'immunoprecipitation demontrent que la novobiocine ne perturbe pas l'activite de HSF1 en dissociant la Hsp90 de HSF1 monomerique ou trimerique, suggerant que l'effet de la novobiocine sur HSF1 soit du a des modifications de l'autophosphorylation de la Hsp90. La geldanamycine se lie au site ATPase N-terminal de la Hsp90 et inhibe son activite chaperon. Un traitement des ovocytes a la geldanamycine resulte en une augmentation de la stabilite des trimeres HSF1 actifs de facon dependante de la concentration durant un choc thermique suboptimal, et retarde le desassemblage des trimeres durant la periode de recuperation. Ces resultats suggerent que l'activite chaperon de la Hsp90 est requise au desassemblage des trimeres HSF1. Les resultats obtenu avec la novobiocine suggerent que l'activite de liaison de l'ATP de l'extremite C-terminale de la Hsp90 est requise aux etapes initiales de la trimerisation de HSF1, alors que les effets de la geldanamycine suggerent que les activites ATPase et chaperon de l'extremite N-terminale sont requises au desassemblage des trimeres actives. Ces resultats fournissent un apercu important des mecanismes moleculaires par lesquels les inhibiteurs pharmacologiques de la Hsp90 affectent la reponse au choc thermique. Mots-cles : HSF1, Xenopus, novobiocine, geldanamycine. [Traduit par la Redaction], Introduction In nature, organisms endure environmental stresses through induction of responses at the molecular level that promote survival. Heat shock proteins (Hsps) are molecular chaperones involved in protein biosynthesis, folding, [...]

Previous work has shown that purified double mutant A204C/C374A yeast actin is polymerization-deficient in vitro under physiological concentrations. To understand the importance of the 204 residue in subdomain 4, a series of actin proteins with a single mutation at this position were created with Cys-374 retained. Only yeast expressing A204G-, A204S-, or A204C-actin were viable. The A204G and A204S strains were sensitive to cold temperature and hyperosmolarity, whereas the A204C strain showed more profound effects on growth under these conditions. Cells expressing A204Cactin exhibited anomalies previously observed for A204C/C374A actin, including abnormal actin structures. A204G- and A204S-actin proteins had 12- and 13-fold increased critical concentrations, respectively, relative to wild-type. Only at very high concentrations could A204C actin polymerize when ATP was bound; when hydrolyzed, the ADP-containing A204C filaments depolymerized, demonstrating a profound difference in critical concentration between ATP and ADP states with A204C actin. A correlation between size of the residue substituted at position 204 and energy minimization of actin filament models was observed. We propose that the region surrounding residue 204 is involved in interactions that change depending on the phosphorylation state of the bound nucleotide that might reflect different conformations of F-actin subunits. Key words: actin polymerization, mutagenesis, critical concentration, nucleotide. Des travaux anterieurs ont montre que le double mutant purifie A204C/C374A de l'actine de levure possede un defaut de polymerisation in vitro sous des conditions physiologiques. Afin de comprendre l'importance du residu 204 du sous-domaine 4, une serie de proteines comportant une mutation ponctuelle a cette position ont ete produites, en conservant la Cys-374. Seules les levures exprimant les formes A204G, A204S ou A204C de l'actine etaient viables. Les souches A204G et A204S etaient sensibles au froid et a l'hyperosmolarite, alors que la souche A204C montrait des problemes de croissance plus prononces sous ces conditions. Les cellules exprimant l'actine A204C montraient des anomalies deja observe es chez les cellules exprimant la forme A204C/C374A, incluant des structures anormales d'actine. Les proteines A204G et A204S possedaient des concentrations critiques respectivement 12 et 13 fois superieures, relativement au type sauvage. L'actine A204C ne polymerisait qu'a tres haute concentration lorsque l'ATP etait liee; apres hydrolyse, les filaments d'actine A204C contenant l'ADP depolymerisaient, demontrant l'existence d'une difference importante dans les concentrations critiques des formes liees a l'ATP et a l'ADP de l'actine A204C. Une correlation entre la taille des residus substitues en position 204 et la minimisation d'energie des modeles de filaments d'actine a ete observee. Nous proposons que la region environnant le residu 204 est impliquee dans les interactions qui changent selon l'etat de phosphorylation du nucleotide lie, refletant possiblement differentes conformations des sous-unites d'actine. Mots-cles : polymerisation de l'actine, mutagenese, concentration critique, nucleotide. [Traduit par la Redaction], Introduction Actin is a 42 kDa cytoskeletal protein involved in a plethora of physiological processes. Polymerization into long filaments (F-actin) is a fundamental activity of the actin protein. F-actin can [...]