Is biofuel policy harming biodiversity in Europe?

We assessed the potential impacts of land-use changes resulting from a change in the current biofuel policy on biodiversity in Europe. We evaluated the possible impact of both arable and woody biofuel crops on changes in distribution of 313 species pertaining to different taxonomic groups. Using species-specific information on habitat suitability as well as land use simulations for three different biofuel policy options, we downscaled available species distribution data from the original resolution of 50 to 1 km. The downscaled maps were then applied to analyse potential changes in habitat size and species composition at different spatial levels. Our results indicate that more species might suffer from habitat losses rather than benefit from a doubled biofuel target, while abolishing the biofuel target would mainly have positive effects. However, the possible impacts vary spatially and depend on the biofuel crop choice, with woody crops being less detrimental than arable crops. Our results give an indication for policy and decision makers of what might happen to biodiversity under a changed biofuel policy in the European Union. The presented approach is considered to be innovative as to date no comparable policy impact assessment has been applied to such a large set of key species at the European scale.     

Bridging the morphological and biological species concepts: studies on the Bactrocera dorsalis (Hendel) complex (Diptera: Tephritidae: Dacinae) in South-east Asia

Defining species accurately is a critical need in fundamental disciplines such as ecology and evolutionary biology and in applied arenas such as pest management. The validity of species designations depends on agreement of different methods of species diagnosis for unique biological species. The Bactrocera dorsalis complex of fruit flies provide an excellent opportunity for such a test of the congruence of different techniques (e.g. morphological, molecular, host-plant based, chemotaxonomy) used for species diagnosis. The complex contains a large number of closely-related species, is distributed over a wide geographical range in South-east Asia and considerable information has been compiled on some species. In the present study, the morphological and biological species boundaries were compared using new data from morphometric analyses of reproductive and body parts, together with a review of data on morphology, chemistry of male pheromones that are important in courtship and mating, molecular analyses, and endemic rainforest host plants. For the populations studied ( Bactrocera carambolae , Bactrocera dorsalis , Bactrocera occipitalis , Bactrocera papayae , Bactrocera philippinensis , Bactrocera kandiensis and Bactrocera invadens ) there appears to be significant congruence between the morphological and biological species boundaries.  © 2008 The Linnean Society of London, Biological Journal of the Linnean Society , 2008, 93 , 217–226.     

Can macroinvertebrate rapid bioassessment methods be used to assess river health during drought in south eastern Australian streams?

• 1 Despite significant concern about drought impacts in Australia, there have been no broad‐scale studies of drought effects on river health. A severe and prolonged drought has been acting on many streams in south eastern Australia over the past decade. EPA Victoria has undertaken rapid bioassessment (RBA) of over 250 stream reference sites since 1990, providing an opportunity for a before‐after‐control‐impact investigation of drought related changes to macroinvertebrate indices and water quality. This study uses data from 1990 to 2004 to critically evaluate the effectiveness of using RBA methods and indices, which were designed for assessment of human impacts, for monitoring streams during drought.
• 2 Reference stream sites across Victoria (those with minimal anthropogenic disturbances and repeatedly sampled) were classified as being ‘in drought’ or ‘not in drought’ using the Bureau of Meteorology’s rainfall deficiency definition. Four biological indices (SIGNAL, EPT, Family Richness and AUSRIVAS) were calculated for combined autumn and spring samples for edge and riffle habitats for the selected sites.
• 3 General linear models and paired t‐tests were used to detect drought related changes to index and water quality values at state‐wide and bioregional scales. Changes in taxa constancy were examined to determine which taxa were sensitive to or benefited from drought conditions. Frequency of site failure against biological objectives specified in the State Environment Protection Policy (Waters of Victoria) (herein termed ‘SEPP WoV’) before and during drought was also examined to detect changes in a management context.
• 4 Few significant changes in index values were detected for riffle habitat samples. Rates of failure against biological objectives were similar before and during drought for riffle samples. In contrast, edge habitat AUSRIVAS and SIGNAL scores were significantly reduced at the state‐wide scale and most indices showed significant declines in the lower altitude forests, and foothills and coastal plains bioregions.
• 5 Generally, more pollution tolerant, lentic taxa replaced sensitive and flow‐requiring taxa in edge samples during drought. In contrast, there were few reductions in the taxa of riffle samples during drought. However, many pool preferring, but pollution sensitive taxa occurred more frequently in riffle areas. Hence, the riffle community began to resemble that of pools and edges. This was attributed to decreased flow and increased ‘lentic’ habitat opportunities in riffles.
• 6 Detection of a drought effect was confined to the edge habitat and site failure could be assigned to drought and anthropogenic impacts, in conjunction or alone. The riffle sampling protocol was resistant to detection of drought effects as samples were only taken when sufficient water was present within this habitat. Therefore, biological changes at sites not meeting policy objectives for riffle habitats can be attributed to anthropogenic rather than drought impacts.

     

Microsatellite loci in the eastern form of the giant freshwater prawn (Macrobrachium rosenbergii)

Six microsatellite loci were identified and characterized in the eastern form of the widespread and commercially important giant freshwater prawn (Macrobrachium rosenbergii). The loci were detected by randomly screening for dinucleotide and trinucleotide repeat units within a partial genomic library developed for the species. In a sample of 29 prawns, number of alleles and heterozygosity per locus ranged from 12 to 18 and from 0.66 to 0.90, respectively. These markers provide powerful tools for the conservation and management of wild stocks, the improvement of cultured stocks of M. rosenbergii, and for investigating evolutionary processes underlying genetic divergence among populations.     

THE COMMUNICATIVE SIGNIFICANCE OF TONALITY IN BIRDSONG: RESPONSES TO SONGS PRODUCED IN HELIUM

ABSTRACT

“Pure tones” are a distinctive acoustic feature of many birdsongs. Recent research on songbird vocal physiology suggests that such tonal sounds result from a coordinated interaction between the syrinx and a vocal filter, as demonstrated by the emergence of harmonic overtones when a bird sings in helium. To investigate the communicative significance of vocal tract filtration in the production of birdsong, we used field playback experiments to compare the responses of male swamp sparrows Melospiza georgiana to normal songs and those same songs recorded in helium. We also measured responses to pure tone songs that had been shifted upward in frequency to match the average spectra of those songs with added harmonics. Male sparrows were significantly more responsive to the playback of normal songs than to either helium songs with added harmonics or frequency- shifted pure tone songs. Songs with harmonics retained a high degree of salience, however. We conclude that explanations for the occurrence of tonal sounds in birdsongs must consider perceptual attributes of songs as communicative signals, as well as problems of song production and transmission.     

N,N –Disubstituted piperazines and homopiperazines: Synthesis and affinities at α4β2* and α7* neuronal nicotinic acetylcholine receptors

A series of N, N– disubstituted piperazines and homopiperazines were prepared and evaluated for binding to natural α4β2* and α7* neuronal nicotinic acetylcholine receptors (nAChRs) using whole brain membrane. Some compounds exhibited good selectivity for α4β2* nAChRs and did not interact with the α7* nAChRs subtype. The most potent analogs were compounds 8-19 (K_i = 10.4 μM), 8–13 (K_i = 12.0 μM), and 8–24 (K_i = 12.8 μM). Thus, linking together a pyridine π-system and a cyclic amine moiety via a homopiperazine ring affords compounds with low affinity but with good selectivity for α4β2* nAChRs.     

Rapid cooling triggers forisome dispersion just before phloem transport stops

Phloem transport stops transiently within dicot stems that are cooled rapidly, but the cause remains unknown. Now it is known that (1) rapid cooling depolarizes cell membranes giving a transient increase in cytoplasmic Ca²⁺, and (2) a rise of free calcium triggers dispersion of forisomes, which then occlude sieve elements (SEs) of fabacean plants. Therefore, we compared the effects of rapid chilling on SE electrophysiology, phloem transport and forisomes in Vicia faba. Forisomes dispersed after rapid cooling with a delay that was longer for slower cooling rates. Phloem transport stopped about 20 s after forisome dispersion, and then transport resumed and forisomes re‐condensed within similar time frames. Transport interruption and forisome dispersion showed parallel behaviour – a cooling rate‐dependent response, transience and desensitization. Chilling induced both a fast and a slow depolarization of SE membranes, the electrical signature suggesting strongly that the cause of forisome dispersion was the transient promotion of SE free calcium. This apparent block of SEs by dispersed forisomes may be assisted by other Ca²⁺‐dependent sealing proteins that are present in all dicots.     

Salamander Dispersal Across a Forested Landscape Fragmented by a Golf Course

Abstract: We assessed dispersal behavior of 78 radiotagged adult spotted salamanders (Ambystoma maculatum) at a 36-hole golf course in southeastern Connecticut, USA. Lake of Isles Golf Course is atypical of most golf courses in North America because it is much larger (461 ha) than average 18-hole golf courses (54 ha) and deciduous forests accounted for 70% landscape composition on the course. We tracked individuals an average of 164 days as they emigrated from 3 seasonal pools surrounded by golf course fairways and one pool located in contiguous forest (control pool) from March through December 2004. Males and females dispersed similar distances at the control pool, averaging 71 ± 10 m. However, females migrating across the golf course dispersed twice as far (214 ± 25 m) as males on the golf course (102 ± 15 m) and both genders at the control pool. Over 40% the salamanders at the golf course crossed fairways; thus, fairways were not a dispersal barrier to adult spotted salamanders. Previous researchers have suggested establishing a 164-m life zone around breeding ponds to protect pond-breeding amphibian populations. Our results suggest that strategies that protect core upland habitat within 164 m of wetland boundaries would include 82% of adult males and only 50% of adult females. Empirical estimates based on our telemetry study suggest that core terrestrial habitat would have to extend 370 m to protect 95% of adult females, which is much farther than previous estimates.