Riparian Habitat

The ecological environment of three aquatic rodents was studied in the French Ardennes region. Two species, the coypu (Myocastor coypus) and the common muskrat (Ondatra zibethicus), are invasive. By contrast the native European beaver (Castor fiber) was extirpated from the region, subsequently reintroduced, and currently is protected. The aim of this study was to compare the ecological requirements of these three species and predict their future range distributions. We studied the relationship between the species and describe the characteristics of waterways and riparian vegetation in 29 sampling sites. Coypus and muskrats were observed in a variety of riparian habitats and their probability of detection appeared to be independent of waterway width, bank height or bank slope. The availability of numerous herbaceous plants, known to be consumed by these species, may facilitate their settlement. Muskrats are widespread on the French Ardennes waterways, but coypus have not yet colonised the northern part of the region. On the other hand, the beaver was observed primarily in the widest waterways with high banks, where woody plant species, such as Betula, Carpinus and Fraxinus, are found in abundance. Potentially favourable sites for beaver and coypu settlement were analysed to suggest appropriate management according to each species’ status. However, the number of sample sites is weak, especially for sites with beaver, limiting our conclusion.

Lapwai Creek, an agriculturally impacted stream in northern Idaho, was examined to determine longitudinal patterns of particulate allochthonous input from different riparian vegetation types. The stream, characterized by extensive removal of mature vegetation, was classified as having four riparian vegetation types: herbaceous, herbaceous-shrub mix, shrubs, and deciduous trees. Litterfall from each vegetation type was measured monthly for two years at

Macroinvertebrates are one of the key components of lake ecosystems and are required to be monitored alongside other biological groups to define ecological status according to European Union legislation. Macroinvertebrate communities are highly variable and complex and respond to a diverse series of environmental conditions. The purpose of this study was to examine the relative importance of environmental variables in explaining macroinvertebrate abundance. A total of 45 sub-alpine lakes were sampled for macroinvertebrates in the shallow sublittoral. Environmental variables were grouped into four types: (1) aquatic physical and chemical parameters, (2) littoral and riparian habitat, (3) lake morphometric parameters and (4) sediment chemical characteristics. Nonparametric multiplicative regression (NPMR) was used to model the abundance of individual macroinvertebrate taxa. Significant models were produced for nine out of the 24 taxa examined. Sediment characteristics were the group most frequently included in models and also the factors to which taxa abundance was the most sensitive. Aquatic physical and chemical variables were the next group most frequently included in models although chlorophyll a was not included in any of the models and total phosphorus in only one. This indicates that many taxa may not show a direct easily interpretable response to eutrophication pressure. Lake morphometric factors were included in several of the models although the sensitivity of macroinvertebrate abundance tended to be lower than for sediment and aquatic physical and chemical factors. Habitat factors were only included in three models although riparian vegetation was found to have a significant influence on the abundance of Ephemera danica indicating that ecotone integrity is likely to play a role in its ecology. Overall, the models tended to be specific for species with limited commonality across taxa. Models produced by NPMR indicate that the response of macroinvertebrates to environmental variables can be successfully described but further research is required focussing in more detail on the response of key taxa to relevant environmental parameters and anthropogenic pressures.

Keywords Lake macroinvertebrates - Sub-alpine lakes - Nonparametric multiplicative regression - Water Framework Directive

Because riparian forest strips are perceived to buffer aquatic ecosystems from logging-related disturbance, they are usually not harvested. However, their value as refuges for terrestrial wildlife is unknown. We conducted two live-trapping experiments in the riparian zone adjacent to rivers in a boreal balsam fir (Abies balsamea) forest in Quebec. In the first experiment, we compared late summer use, during

The marsh deer is the largest neotropical cervid with morphological and ecological adaptations to wetlands and riparian habitats. Historically, this now endangered species occupied habitats along the major river basins in South America, ranging from southern Amazonia into northern Argentina to the Paraná river delta. This particularly close association with wetlands makes marsh deer an excellent species for studying the effects of Pleistocene climatic changes on their demographic and phylogeographic patterns. We examined mitochondrial DNA variation in 127 marsh deer from 4 areas distributed throughout the Río de la Plata basin. We found 17 haplotypes in marsh deer from Brazil, Bolivia and Argentina that differed by 1–8 substitutions in a 601 bp fragment of mitochondrial control region sequence, and 486 bp of cytochrome b revealed only 3 variable sites that defined 4 haplotypes. Phylogeny and distribution of control region haplotypes suggest that populations close to the Pantanal area in central Brazil underwent a rapid population expansion and that this occurred approximately 28,000–25,000 years BP. Paleoclimatic data from this period suggests that there was a dramatic increase for precipitation in the medium latitudes in South America and these conditions may have fostered marsh deer’s population growth.

The severe loss or degradation of riparian habitats has led to their impoverishment and impaired function, which may have severe consequences on both the riparian habitats themselves and their associated biota, including mammalian carnivores. We selected 70 riparian habitat reaches to evaluate the condition of the riparian habitats in southern Portugal and their use by carnivores. These sites were assessed for riparian condition using the stream visual assessment protocol (SVAP) and surveyed for carnivore presence along the riparian zones and across the surrounding matrix landscape, both in the wet (winter) and the dry (summer) season. Results show that carnivore surveys adjacent to riparian habitats consistently had significantly higher species richness than the matrix habitats, in both sampling seasons. Carnivore relative abundance and relative abundance of stone marten, common genet and Egyptian mongoose also showed higher values in riparian habitats, with significant differences in at least one season. The Eurasian badger, on the other hand, showed higher relative abundance values in the landscape matrix, though differences were not significant. The SVAP index ranked about 83% riparian reaches as poor or fair condition, and species richness was significantly higher in fair condition reaches during the wet season. These results reflect the importance of riparian habitats in Mediterranean ecosystems for mammalian carnivores. However, the generalized poor condition of these habitats suggests that direct measures for riparian restoration could be appropriate. The preservation or improvement of riparian habitats would certainly benefit the mammalian carnivore populations and consequently their conservation.