Methods to Reduce Avian Bycatch in Small Mammal Studies Using Snap Traps

ABSTRACT Avian bycatch, a common and undesired occurrence in small mammal studies, should be minimized by researchers. We examined effects of trap covering, treadle color (copper or yellow plastic), trap size (mouse or rat), and trap weathering (traps <1 yr or ≥ 1 yr old) on avian bycatch during 3 years. We found that covered traps caught 81% fewer birds and 70% fewer small mammals than did uncovered traps, that mouse traps caught 30% more birds and 38% more small mammals than did rat traps, and no capture differences for treadle color or trap weathering. Covered traps effectively reduced avian bycatch and should be used when reduced small-mammal capture rates are acceptable.     

Conservation management of Pinus palustris ecosystems from a landscape perspective

Question: Do case studies from silvicultural and restoration studies and applied conservation management in second‐growth Pinus palustris stands provide unique insights for conservation models? Methods: A review of management paradigms that conserve the high biological diversity and rare species, drawn from characteristics in both second‐growth and old‐growth stands, is presented for fire‐maintained Pinus palustris (longleaf pine) forests. Results: A common assumption that old‐growth stands provide the primary information for the development of conservation management strategies de‐emphasizes lessons learned from second‐growth and restoration studies. Primary conservation management goals for the Pinus palustris ecosystem include the perpetual regeneration of the fire‐maintained forest and conservation of the characteristically high biological diversity and rare species. Several attributes, such as a sustained population of Picoides borealis (red‐cockaded woodpecker), Aristida stricta (wiregrass)‐dominated ground cover, and undisturbed upland‐wetland ecotones, can predict a diverse and ecologically functional ecosystem. Such indicators are linked to critical structural and functional features of the system and reflect previous land management histories that suggest sustainable approaches. Conclusions: A traditional definition of ‘old‐growth’ relying on overstorey may be limited in describing important features of healthy, diverse Pinus palustris ecosystems. Some characteristics are significantly more important for maintenance of diversity than age of the trees and these features may be present in old‐ or second‐growth forests. We advocate that the management history, structural characteristics and landscape context of stands that harbour desirable conservation attributes (red‐cockaded woodpeckers, wiregrass, gopher tortoises and undisturbed upland‐wetland ecotones) can be used as indicators to identify important conservation and forest management principles.     

Quantifying uncertainty from large-scale model predictions of forest carbon dynamics

Linking environmental computer simulation models and geographic information systems (GIS) is now a common practice to scale up simulations of complex ecosystem processes for decision support. Unfortunately, several important issues of upscaling using GIS are rarely considered; in particular scale dependency of models, availability of input data, support of input and validation data, and uncertainty in prediction including error propagation from the GIS. We linked the biogeochemical Forest‐DNDC model to a GIS database to predict growth of Eucalyptus globulus plantations at two different scales (～0.045 ha plot^?1 scale and ～100 ha grid^?1 scale) across Victoria, in south‐eastern Australia. Results showed that Forest‐DNDC was not scale dependent across the range of scales investigated. Reduced availability of input data at the larger scale may introduce severe prediction errors, but did not require adjustment of the model in this study. Differences in the support of input and validation data led to an underestimation of predictive precision but an overestimation of prediction accuracy. Increasing data support, produced a high level of prediction accuracy (^?e%), but a medium level of predictive precision (r²=0.474, ME=0.318) after statistical validation. GIS error contribution could be detected but was not readily or reliably quantified. In a regional case study for 2653 ha of E. globulus plantations, the linked model GIS system estimated a total standing biomass of 95 260 t C for mid‐2003 and a net CO₂ balance of ?45 671 t CO₂‐C yr^?1 for the entire year of 2002. This study showed that regional predictions of forest growth and carbon sequestration can be produced with greater confidence after a comprehensive assessment of upscaling issues.     

Low frequency of infertility among workers in a borate processing facility

In order to rule out the possibility of omitting some individuals in the study at field visits described in previous articles, either because of the reluctance of the subject or because of his appointment elsewhere, fertility and infertility states of borate workers of the Borax and Acid Plants in Bandirma, Balikesir are given. Balikesir is one of the four provinces with large borate deposits of Turkey, and Bandirma is 1 of its 19 districts. This county is relatively far away from borate deposits, and drinking water piped out through the springs has a boron amount between 0.10 and 0.82 ppm B. That the participants are occupationally exposed to the mineral in essence is therefore conceivable. At the first phase of the investigation, 191 workers were interviewed, as detailed previously. Among these, there were six infertiles of the primary type with a rate 3.1%. Boron-unrelated infertile couples among sibs were found to be 2.6–3.6%, and 3.2% for three-generation marriages—none being higher than those revealed in different sets of controls. In the second stage of work, computerized files of all workers of the facility and all employees of the general management sharing the same location were checked without an interview. Twenty-four subjects (3.4%) out of 712 workers were childless versus 2.7% among 108 employees, and 2.2% among 91 workers of a distantly located sulfuric acid plant of the same complex. The differences were not significant, and these recent findings support the conclusion already reached almost unambiguously that boron exposure at the present levels does not interfere with human reproduction.     

Pest suppression by bats and management strategies to favour it: a global review

Fighting insect pests is a major challenge for agriculture worldwide, and biological control and integrated pest management constitute well-recognised, cost-effective ways to prevent and overcome this problem. Bats are important arthropod predators globally and, in recent decades, an increasing number of studies have focused on the role of bats as natural enemies of agricultural pests. This review assesses the state of knowledge of the ecosystem services provided by bats as pest consumers at a global level and provides recommendations that may favour the efficiency of pest predation by bats. Through a systematic review, we assess evidence for predation, the top-down effect of bats on crops and the economic value of ecosystem services these mammals provide, describing the different methodological approaches used in a total of 66 reviewed articles and 18 agroecosystem types. We also provide a list of detailed conservation measures and management recommendations found in the scientific literature that may favour the delivery of this important ecosystem service, including actions aimed at restoring bat populations in agroecosystems. The most frequent recommendations include increasing habitat heterogeneity, providing additional roosts, and implementing laws to protect bats and reduce agrochemical use. However, very little evidence is available on the direct consequences of these practices on bat insectivory in farmland. Additionally, through a second in-depth systematic review of scientific articles focused on bat diet and, as part of the ongoing European Cost Action project CA18107, we provide a complete list of 2308 documented interactions between bat species and their respective insect pest prey. These pertain to 81 bat species belonging to 36 different genera preying upon 760 insect pests from 14 orders in agroecosystems and other habitats such as forest or urban areas. The data set is publicly available and updatable.     

Diversity and ecology of wood-inhabiting aphyllophoroid basidiomycetes on fallen woody debris in various forest types in Switzerland

This study on the ecology of aphyllophoroid wood-inhabiting basidiomycetes in Switzerland showed a remarkably high species diversity of both saprophytes and mycorrhiza-forming species. Phlebiella vaga, a saprophytic species, and Amphinema byssoides, a mycorrhizal symbiont, were the two most abundant species. A total of 3339 samples of fungal fruitbodies in 86 plots distributed all over Switzerland belonged to 238 species. The five main biogeographical regions of Switzerland showed different pattern of fungal species richness: while the Plateau at lower altitudes was found to be rather rich, the Northern Alps and Central Alps, with the highest amount of forests cover, yielded less species. Although the Southern Alps exhibited the lowest species richness, this region harbours a specific species set. These findings encourage for further studies in Central Europe, where many species of aphyllophoroid wood-inhabiting basidiomycetes seem to be highly under-investigated.     

Social versus individual behaviour: a comparative approach to thermal behaviour of the honeybee (Apis mellifera L.) and the American cockroach (Periplaneta americana L.)

To study the relationship between the individual and social thermoregulatory behaviour, we used honeybee workers and American cockroaches. Single insects or groups of 10-20 individuals were placed in a temperature gradient chamber, and their thermal preference was recorded for 48 h under natural summer photoperiod. Single bees showed diurnal changes in selected ambient temperature, which culminated at 14:00 reaching 34+/-2 degrees C, and then slowly decreased, reaching a nocturnal minimum of 28+/-2 degrees C at 04:00. In contrast, the zenith of temperature selected by groups of bees (31+/-1 degrees C) was reached at 04:00 and the nadir (29+/-2 degrees C) was recorded at 14:00. Groups of bees clustered together during the night time, and dispersed during intense day time activity. Such changes were absent in groups of cockroaches. Cockroaches selected an ambient temperature of 30+/-1 degrees C both during day and night. In conclusion, there is a striking analogy in the diurnal thermal behaviour between a colony of bees and mammals. During their nychthemeral rest phase, both of them select higher temperatures than during the activity phase and, simultaneously, they reduce their overall surface area of heat loss to conserve metabolic heat. Therefore, the colony behaves as a homeothermic superorganism. In contrast, a single bee, isolated from the colony, utilizes a heterothermic strategy to save energy for a morning warm up.