Habitat associations of pool-breeding amphibians in eastern Massachusetts,USA

There is a pressing need to develop a sound conservation strategy for pool-breeding amphibians, which includes gaining a better understanding of the habitat and landscape-scale characteristics associated with populations. To investigate relationships between amphibian species richness and characteristics of breeding pools and surrounding landscapes, we surveyed 85 pools in eastern Massachusetts (USA) in 1996 and 1997. A total of 11 species was detected, with most pools having 2–5 species. Pools were typically small, 77.6% were <0.2 ha, but most pools (72%) had hydroperiods that persisted at least into August in most years. Based on linear regression analyses, species richness was positively associated with three within-pool variables (pool surface area, hydroperiod, and the amount of emergent vegetation), and a landscape-level variable (presence of another breeding pool within 1 km), while one within-pool variable (tree canopy cover) exhibited a significant negative association with species richness. These within-pool habitat variables and connectivity to other breeding pools are important characteristics to consider when attempting to identify breeding sites that could provide core habitat in conservation reserves designed for the conservation of pool-breeding amphibian species richness. Conservation reserves for pool-breeding amphibian populations should include pool complexes functioning as habitat for metapopulations. Core pool habitats within such reserves should be large (0.5–1.0 ha), with seasonal hydroperiods that persist into August or that dry in some years, and with sufficient emergent vegetation to provide diverse microhabitats and refugia.     

The germination process in vernal pools: sensitivity to environmental conditions and effects on community structure

Variation in timing and amount of rainfall in California has been noted to cause strong year-to-year differences in the composition of vernal pool communities. We explored the effects of possible variation of the “rainy season” in a seedbank germination study conducted with three factors: monthly timing of first soil moistening, length of moist period before inundation, and length of inundation. Monthly timing was the most important factor in determining the number of plants and number of species that germinated in the pots. Many species, mostly generalist wetland and pool-endemic species, showed sharp decreases in number in later trials. Five species did not germinate in the final trial, and two of these were abundant only in the first trial. Inundation was required for the germination of two species. Treatments with a combination of inundated and moist conditions resulted in higher numbers of species and numbers of plants compared to treatments with only moistness or only inundation. Our results indicate that vernal pool species have mechanisms that keep them from emerging under unfavorable conditions. The sensitivity of vernal pool species to out-of-season germination suggests that they could be negatively affected by climatic change, with generalist species like non-native Lythrum hyssopifolium having a potential advantage. Received: 15 July 1996 / Accepted: 14 July 1997     

Hydroperiods of created and natural vernal pools in central Ohio: A comparison of depth and duration of inundation

Water levels were recorded weekly from six natural vernal pools and 10 created vernal pools at two forested wetland complexes in central Ohio. Vernal pool median water depth and duration of inundation were significantly greater at the created vernal pools than at the natural vernal pools (α = 0.05, P < 0.05). The average period of inundation for created pools was 309 ± 32 days, compared with 250 ± 16 days for natural pools. The created pools produced a range of inundation times, from 163 to 365 days in length, with three pools permanently inundated.     

Lower Jurassic Arthropod Resting Trace from the Hartford Basin of Massachusetts,USA

Cheliceratichnus lockleyi ichnogen. nov. et ichnosp. nov. is a new ichnotaxon of arthropod resting trace (cubichnium) from the Lower Jurassic (Hettangian) East Berlin Formation in Holyoke, Massachusetts, USA. The trace fossil is preserved as showing many of the external anatomical features of the exoskeleton, which resemble those of some chelicerates, notably sun spiders (Solifugae). The resting trace is directly associated with a trackway of the ichnospecies Acanthichnus cursorius Hitchcock. This is the first described fossil resting trace of a solifugan-like arthropod, and the first direct evidence of a trackmaker of A. cursorius.     

Hygrophorus yukishiro sp. nov., a new vernal edible mushroom from Nagano Prefecture,Japan

A novel basidiomycetous species, Hygrophorus yukishiro, is described from Japan. The basidiomata of this fungus have been referred to as “yuki-shiro”, “yuki-take”, and “yuki-wari”, and used as an edible mushroom in the central region of Nagano, Japan. Hygrophorus yukishiro fruits in the early spring season under oak-dominated stands. Morphological and phylogenetic analyses of the internal transcribed spacer region of the nuclear ribosomal RNA gene indicated that H. yukishiro is a sister species of H. arbustivus and belongs to section Hygrophorus, subsect. Fulventes. Hygrophorus yukishiro is similar in its external morphology and fruiting phenology to H. roseobrunneus, H. leucophaeo-ilicis, and H. roseodiscoideus, but differs in the color and texture of its pileus surface and microscopic characteristics.     

Scoyenia Escape Burrows in Fluvial Pebbly Sand: Upper Triassic Sugarloaf Arkose,Deerfield Rift Basin,Massachusetts, USA

Late Triassic larvae of an insect, probably a beetle, moved diagonally upwards though fluvial pebbly sand along a thin mud layer, constructing Scoyenia burrows in the Sugarloaf Arkose, Deerfield rift basin, Massachusetts. They may have been escaping a temporary rise of the water table in the monsoonal dry season.     

Freshwater rock pools: a review of habitat characteristics,faunal diversity and conservation value

1. In the light of the recent surge of interest in small and often temporary wetlands as model systems for ecological and evolutionary research, this article reviews current knowledge on freshwater rock pools and their fauna. 2. Freshwater rock pools occur all over the globe in all major biomes and depend mainly on precipitation for filling. Rock pool clusters are some of the more persistent and oldest freshwater habitats worldwide. Interactions between climate and geology (e.g. limestone, sandstone, granite) generally determine the morphology and hydrology of rock pool habitats, with hydroperiods ranging from several days up to the whole year. Pool volume is usually small, resulting in strongly fluctuating environmental conditions, low conductivity and wide variations in pH (from 4.0 to 11.0) and temperature (from freezing point to 40 °C) often with well‐marked diel cycles. The highly variable environmental conditions, combined with the unpredictability of the flooding regime, require high stress tolerance of the inhabitants, with adaptations for surviving the dry phase such as the production of resistant stages and active emigration followed by recolonisation. 3. About 460 aquatic animal species have been recorded from freshwater rock pools around the world. Approximately 170 of these are passive dispersers, which mainly disperse as resting stages via wind and overflow of water between pools. Successful long distance dispersal seems limited. This group is composed mainly of rock pool specialists with a high degree of endemicity. The remaining taxa can be considered active dispersers, with migration usually restricted to the adult stage. Often these taxa are broadly distributed and occur in a wide range of temporary habitats in addition to rock pools. 4. The inherent characteristics of freshwater rock pools, such as their simple structure and occurrence on similar substrata all over the world, facilitate comparison of research results and promote rock pools as model systems for ecological and evolutionary research. Nevertheless, despite their potential as model systems, the unique fauna and their importance as sources of freshwater in dry countries, the ecology of freshwater rock pools remain virtually unexplored in large parts of the world.     

Nutrient limitation of phytoplankton growth in Waquoit Bay, Massachusetts, USA: a nutrient enrichment study

We conducted nutrient enrichment experiments and field sampling to address three questions: (1) is there nutrient limitation of phytoplankton accumulation within an estuary whose waters are exposed to relatively high nitrogen loading rates, (2) where in the salinity gradient from fresh to seawater (0 to 32‰) is there a shift from phosphorus to nitrogen limitation of phytoplankton accumulation, and (3) is there a seasonal shift in limiting function of phosphorus and nitrogen anywhere in the estuarine gradient. Nitrogen and phosphorus enrichment experiments in the Childs River, an estuary of Waquoit Bay, Massachusetts, USA, showed that the accumulation of phytoplankton biomass in brackish and saline water was limited by supply of nitrate during warm months. The effects of enrichment were less evident in fresh water, with short-lived responses to phosphate enrichment. There was no specific point along the salinity gradient where there was a shift from phosphorus- to nitrogen-limited phytoplankton accumulation; rather, the relative importance of nitrogen and phosphorus changed along the salinity gradient in the estuary and with season of the year. There was no response to nutrient additions during the colder months, suggesting that some seasonally-varying factor, such as light, temperature or a physiological mechanism, restricted phytoplankton accumulation during months other than May-Aug. There was only slight evidence of a seasonal shift between nitrogen- and phosphorus-limitation of chlorophyll accumulation. Phytoplankton populations in nutrient-rich estuaries with short flushing times grow fast, but at the same time the cells may be advected out of the estuaries while still rapidly dividing, thereby providing an important subsidy to production in nearby deeper waters. This revised version was published online in August 2006 with corrections to the Cover Date.     

Purification and structural characterization of insulin from a caecilian, Typhlonectes natans (Amphibia: Gymnophiona)

Despite the important position of amphibia in phylogeny, efforts at the structural characterization of amphibian neurohormonal peptides have largely been confined to the Anurans (frogs and toads). Insulin was purified from an extract of the pancreas of the caecilian, Typhlonectes natans. The primary structure of the peptide was established as:

A-chain: Gly-Ile-Val-Glu-Lys⁵-Cys-Cys-Leu-Ser-Thr¹⁰-Cys-Ser-Leu-Tyr-Glu¹⁵-Leu-Glu-Ser-Tyr-Cys²⁰-Asn

B-chain: Ile-Ala-Asn-Gln-His⁵-Leu-Cys-Gly-Ser-His¹⁰-Leu-Val-Glu-Ala-Leu¹⁵-Tyr-Leu-Val-Cys-Ala²⁰-Asp-Arg-Gly-Phe- Phe²⁵-Tyr-Thr-Pro-Lys-Ser³⁰

This amino acid sequence contains several unusual substitutions (Gln → Lys at A5, His → Leu at A8, Gln → Glu at A15, and Gly → Ala at B20) that are not present in other amphibian insulins. The structure of insulin appears to be less well conserved among the different orders of amphibia, compared with reptiles and birds.     

Heterotrissocladius boltoni sp.n., a new orthoclad from vernal pools and streams in Ohio,U.S.A. (Diptera: Chironomidae)

Heterotrissocladius boltoni sp.n. from Ohio, U.S.A., is described in both sexes and all stages. The species belongs in themarcidus group and is found in temporary streams and pools     

Developing regional conservation priorities using red lists: a hypothetical example from the Swiss lowlands

This paper investigates how different prioritizations of species for conservation can affect both the number of breeding individuals that receive protection and the distribution of conservation attention among different types of habitat. I use as a study example three red lists of the avifauna of Kanton Zürich in northern Switzerland. Species are weighted based on their placement in different red list categories to represent differences in species' relative conservation value. I examine how these weightings affect the number of breeding pairs benefiting from increasing conservation effort. Conservation effort is defined as the number of ranked land parcels that receive conservation attention, be it through habitat enhancement, protection, or other measures. I rank parcels' conservation value based on the number of weighted breeding pairs estimated for each parcel. Not surprisingly, the number of category-1, -2 and -3 breeding pairs that receive benefits varies greatly when different red lists are used. Changes in the relative conservation value of species in different categories influences both the number of breeding pairs and the number of parcels to receive conservation attention. The effect of increasing conservation effort on the number of breeding pairs and the proportion of each landscape type receiving attention also vary when different red lists and relative conservation values are used to determine conservation priorities. Use of the official red list published by a governmental body (Bundesamt für Umwelt, Wald und Landschaft, Bern, Switzerland) results in more emphasis on conservation in agricultural landscape than did use of either of the other two lists. The process of prioritization of sites for conservation should evaluate the effects of variation in both the relative conservation value of species and species categorization that may arise due to incomplete data and variation in opinion.     

Use of a generalised linear model to test habitat preferences: the example of Zingel asper, an endemic endangered percid of the River Rhône

SUMMARY 1. A study of microhabitat preferences was conducted on Zingel asper , an endangered endemic species from the Rhône catchment. A generalised linear model allowed us to test statistically the non-random habitat selection and the effect of season and site on this habitat selection.
2. The analysis detected significant preferences for the three physical variables considered: water depth, water velocity and substratum size.
3. A seasonal shift in the substratum size preference was found: preference for stones increasing during the spawning season. Depth preference varied between sites, suggesting a possible plasticity in habitat selection.
4. These results suggest that the availability of suitable physical habitat plays a significant role in determining fish distribution in the River Beaume.     

Hainanenins: a novel family of antimicrobial peptides with strong activity from Hainan cascade-frog, Amolops hainanensis

Antimicrobial peptides (AMPs) secreted by amphibian skin represent an important innate immune defense strategy. There are more than 340 species in the family of Ranidae worldwidely, and from which nearly 100 families of AMPs comprising between 8 and 48 amino acid (aa) residues have been characterized. In current work, two novel AMPs were purified from the skin secretion of Hainan cascade-frog, Amolops hainanensis, and 31 cDNA sequences encoding 10 novel AMPs belonging to 4 families were cloned from the constructed skin cDNA library of A. hainanensis. Among these 10 AMPs, 5 peptides represent the prototypes of a novel amphibian AMP family. According to the generic name of the species of origin, they were designated as hainanenin-1-5. Each of them consists of 21 aa residues with a C-terminal disulphide loop of 7 residues between Cys(15) and Cys(21). Two of them (hainanenin-1 and 5) were then synthesized and their in vitro activities were screened, including antimicrobial, hemolytic and antioxidant activities. The results showed that hainanenin-1 and 5 possessed strong and broad-spectrum antimicrobial activities against Gram-positive, Gram-negative bacteria and fungi, including a large number of clinically isolated drug-resistant pathogenic microorganisms, and slight antioxidant activity. Undesirably, hainanenin-1 and 5 exhibited strong hemolytic activity on human erythrocytes. The discovery of hainanenins and their great antimicrobial potency provides new templates for anti-infective agent design.     

Constructing a Wild Mushroom Panopticon: The Extension of Nation-State Control over the Forest Understory in Oregon,USA

Constructing a Wild Mushroom Panopticon: The Extension of Nation-State Control over the Forest Understory in Oregon, USA. For most of the 20^th century, wild mushrooms on national forests in the United States fell under a de facto open-access management regime. As consumer demand for wild mushrooms increased, a nation-state wild mushroom management regime based on the use of disciplinary power emerged on many national forests in the Pacific Northwest region. Data from an ethnographic study conducted during the late 1990s illustrate how the simultaneous application of three core surveillance technologies—categorization, monitoring, and tracking, and the creation of a panopticon surveillance system—enabled the Forest Service to enforce nation-state claims to wild mushrooms. The data indicate that many pickers are unsupportive of the new regulatory system because it has transformed what was once their living space into a working place. Pickers also point out that the system does little to protect or enhance the growth of wild mushrooms. The study supports conclusions from previous studies that disciplinary power techniques play a critical role in the capacity of modern states to extend their control over mobile populations and natural resources.     

Functional characterization and expression analysis of a glutathione transporter, BjGT1, from Brassica juncea: evidence for regulation by heavy metal exposure

Glutathione and its derivatives play an important role in the tolerance of plants against heavy metals. A glutathione transporter, BjGT1 (AJ561120), was cloned and functionally characterized from Brassica juncea, a plant which may be used for phytoremediation. The full‐length BjGT1 cDNA showed homology with the high affinity glutathione transporter HGT1 from Saccharomyces cerevisiae and shares 92% identity with a putative glutathione transporter from A. thaliana (At4g16370). When expressed in the S. cerevisiae hgt1Δ strain, BjGT1 complemented the mutant on medium with glutathione as the only sulphur source and mediated the uptake of [³H]GSH. Immunoblot analysis with a peptide‐specific antiserum directed against a C‐terminal sequence revealed high BjGT1 expression in leaf tissue and relatively low expression in stem tissue, whereas BjGT1 protein was not detectable in root tissue. The amounts of BjGT1 mRNA and protein were analysed during a 6 d exposure of B. juncea to 25 µm Cd(NO₃)₂. BjGT1 mRNA was strongly induced by cadmium in stems and leaves. Unexpectedly, the amount of BjGT1 protein in leaves showed a pronounced decrease with a minimum after 96 h of Cd exposure, followed by partial recovery. The strong regulation of BjGT1 by cadmium suggests a role of this glutathione transporter during heavy metal exposure.     

Variation in sperm morphology of a murine rodent from South‐East Asia: the Greater Bandicoot Rat,Bandicota indica

Thitipramote, N., Suwanjarat, J., Leigh, C. and Breed, W.G. 2011. Variation in sperm morphology of a murine rodent from South‐East Asia: the Greater Bandicoot Rat, Bandicota indica.—Acta Zoologica (Stockholm) 92 : 201–205. In most mammals the male gamete, the spermatozoon, has a fairly consistent, species‐specific shape although in a few species some variability is evident. The present study set out to determine the extent of sperm variability in a population of a South‐East Asian murine rodent, Bandicota indica, that was sampled during both the breeding and non‐breeding periods. We found that, regardless of the time of year when the animals were obtained, males had sperm present in the cauda epididymides but a high degree of variability was always evident including the presence of some grossly abnormal forms. The abundance of abnormal sperm tended to be greater during the non‐breeding period. These animals also have relatively small testes, thus the occurrence of the variable sperm populations is consistent with the hypothesis that depressed levels of intermale sperm competition result in a relaxation of the genetic control of male germ cell maturation during spermiogenesis and thus the production of polymorphic sperm populations.