Low intensity surface fire instigates movement by adults of Calosoma frigidum (Coleoptera, Carabidae)

The genus Calosoma (Coleoptera: Carabidae) is a group of large, sometimes ornate beetles, which often voraciously attack caterpillars. Many studies have reported Calosoma beetles being highly conspicuous during defoliator outbreaks. Based on observations of individual beetle behavior, patterns of activity density and phenology we provide a hypothesis on how environmental cues may synchronize Calosoma activity with periods of high defoliation. We have observed that adults of Calosoma frigidum construct underground burrows similar to those reported to be created by larvae for pupation. We propose that small increases in soil surface temperature caused either by defoliation events or decreased albedo of blackened, burned soil causes beetles to leave their underground burrows and begin foraging. Indirect support for this hypothesis comes from high levels of adult Calosoma frigidum collected in relatively small patches of burned forest (<200m(2)) relative to the surrounding mosaic of unburned forest shortly after a prescribed surface burn.     

Improving photosynthesis and metabolic networks for the competitive production of phototroph-derived biofuels

To improve bioenergy production from photosynthetic microorganisms it is necessary to optimize an extensive network of highly integrated biological processes. Systematic advances in pathway engineering and culture modification have resulted in strains with increased yields of biohydrogen, lipids, and carbohydrates, three bioenergy foci. However, additional improvements in photosynthetic efficiency are necessary to establish a viable system for biofuel production. Advances in optimizing light capture, energy transfer, and carbon fixation are essential, as the efficiencies of these processes are the principal determinants of productivity. However, owing to their regulatory, catalytic, and structural complexities, manipulating these pathways poses considerable challenges. This review covers novel developments in the optimization of photosynthesis, carbon fixation, and metabolic pathways for the synthesis of targeted bioenergy carriers.     

A new species of Henneguya (Myxozoa) in the big-eyed scad (Selar crumenophthalmus) from Hawaii

We describe a new myxozoan, Henneguya akule n. sp., infecting the carangid fish Selar crumenophthalmus in Hawaii. Spores were found only in the aortic bulb, characterized by elliptical capsule with 2 tails, and pyriform polar capsules that angled toward the anterior end of the spore. Polar filaments had 3-4 coils. Parasites were present in apparently healthy fishes and caused no evident gross pathology. On microscopy, parasites evinced a mild inflammatory response in the host characterized by accumulations of eosinophilic fibrillar material around spores and a mononuclear infiltrate in the adventitia of the bulbus arteriosus. Overall prevalence was 20%, and prevalence between 2001 and 2006 ranged from 12 to 27%, but did not differ significantly between years. In contrast, prevalence of infection was highest in south-central Oahu. There was no relationship between infection status and body condition or gender of fish, and infection was absent in the smallest and largest fishes. Phylogenetically, H. akule n. sp. is most closely related to other Henneguya species infecting the heart of marine fishes based on ribosomal DNA analysis. This is the first documentation of a myxozoan parasite in marine fishes from Hawaii.     

Smaller and more numerous harvesting gaps emulate natural forest disturbances: a biodiversity test case using rove beetles (Coleoptera,Staphylinidae)

Aim To evaluate changes in the abundance, species richness and community composition of rove beetles (Coleoptera, Staphylinidae) in response to three configurations of experimental gap cuts and to the effects of ground scarification in early succession yellow birch‐dominated boreal forest. In each experimental treatment, total forest removed was held constant (35% removal by partial cutting with a concomitant decrease in gap size) but the total number of gaps was increased (two, four and eight gaps, respectively), resulting in an experimental increase in the total amount of ‘edge’ within each stand. Location Early succession yellow birch‐dominated forests, Quebec, Canada. Methods Pitfall traps, ANOVA, MIXED procedure in sas ®, post hoc Tukey's adjustment, rarefaction estimates, sum‐of‐squares and distance‐based multivariate regression trees (ssMRT, dbMRT). Results Estimates of species richness using rarefaction were highest in clearcut and two‐gap treatments, decreased in smaller and more numerous gaps and were significantly higher in scarified areas than in unscarified areas. ANOVA indicated a significant impact of harvesting on the overall standardized catch. Post hoc Tukey's tests indicated that the total catch of all rove beetles was significantly higher in uncut forests than in the treated areas. Both sum‐of‐squares and distance‐based multivariate regression trees indicated that community structure of rove beetles differed among treatments. Assemblages were grouped into (a) control plots, (b) four‐ and eight‐gap treatments and (c) two‐gap and clearcut treatments. Main conclusions Rove beetle composition responded significantly to increasing gap size. Composition among intermediate and small‐sized gap treatments (four‐ and eight‐gap treatments) was more similar to uncut control forests than were larger gap treatments (two‐gap) and clearcuts. Effects of scarification were nested within the harvested treatments. When the total area of forest removed is held constant, smaller, more numerous gaps are more similar to uncut control stands than to larger gaps and falls more closely within the natural forest heterogeneity.     

Phase shift from a coral to a corallimorph-dominated reef associated with a shipwreck on Palmyra atoll

Coral reefs can undergo relatively rapid changes in the dominant biota, a phenomenon referred to as phase shift. Various reasons have been proposed to explain this phenomenon including increased human disturbance, pollution, or changes in coral reef biota that serve a major ecological function such as depletion of grazers. However, pinpointing the actual factors potentially responsible can be problematic. Here we show a phase shift from coral to the corallimorpharian Rhodactis howesii associated with a long line vessel that wrecked in 1991 on an isolated atoll (Palmyra) in the central Pacific Ocean. We documented high densities of R. howesii near the ship that progressively decreased with distance from the ship whereas R. howesii were rare to absent in other parts of the atoll. We also confirmed high densities of R. howesii around several buoys recently installed on the atoll in 2001. This is the first time that a phase shift on a coral reef has been unambiguously associated with man-made structures. This association was made, in part, because of the remoteness of Palmyra and its recent history of minimal human habitation or impact. Phase shifts can have long-term negative ramification for coral reefs, and eradication of organisms responsible for phase shifts in marine ecosystems can be difficult, particularly if such organisms cover a large area. The extensive R. howesii invasion and subsequent loss of coral reef habitat at Palmyra also highlights the importance of rapid removal of shipwrecks on corals reefs to mitigate the potential of reef overgrowth by invasives.     

Relating tumor score to hematology in green turtles with fibropapillomatosis in Hawaii

The relationship between hematologic status and severity of tumor affliction in green turtles (Chelonia mydas) with fibropapillomatosis (FP) was examined. During 1 wk periods in July 1997 and July 1998, we bled 108 free-ranging green turtles from Pala'au (Molokai, Hawaii, USA) where FP is endemic. Blood was analyzed for hematocrit, estimated total solids, total white blood cell (WBC) count and differential WBC count. Each turtle was assigned a subjective tumor score ranging from 0 (no visible external tumors) to 3 (heavily tumored) that indicated the severity of FP. There was a progressive increase in monocytes and a decrease in all other hematologic parameters except heterophils and total numbers of white blood cells as tumor score increased. These data indicate that tumor score can relate to physiologic status of green turtles afflicted with FP, and that tumor score is a useful field monitor of severity of FP in this species.