Biology subjects

Wolter, C.

Publications and source records attributed to Wolter, C..

3 recordsLinked to original sources

bioRxiv2026

Eyes on the prize: Mice deploy task-driven saccades during naturalistic foraging

Active sensing allows organisms to shape incoming sensory information through self-generated actions, and saccadic eye movements provide a key readout of this process in vision. In primates, saccades are strongly modulated by cognitive variables such as uncertainty, value, and behavioural goals, particularly in complex, naturalistic settings. In rodents, by contrast, saccades have largely been interpreted as reflexive or compensatory, and evidence that they are modulated by cognitive state, such as trial outcome, expectation, or task demands, has remained sparse. Here, we examined how mice use saccades during a vision-dependent foraging task in a traversable immersive virtual environment with naturalistic stimuli. We correlated their saccade dynamics with behavioural strategies observed within the virtual environment. Target-directed saccades emerged specifically when informative sensory evidence was available, but also occurred anticipatorily when animals could rely on previously learned spatial contingencies, indicating that saccades were guided not only by immediate visual input but also by internal representations. Strikingly, the temporal structure of inter-saccade intervals resembled signatures previously reported in primates and lengthened with increased processing demand following changes in task contingencies. Together, these findings show that mouse saccades are not merely reflexive gaze corrections, but form part of a cognitively modulated active sampling strategy. More broadly, they suggest that key principles of active visual sensing may be conserved across species and establish mouse oculomotor behaviour as a tractable readout of internal cognitive state.

neuroscience↗

bioRxiv2019

Impact of recreational fisheries on aquatic and riparian biodiversity in artificial lake ecosystems: implications for conservation

Humanity is facing a biodiversity crisis, with freshwater-associated biodiversity in a particularly dire state. Novel ecosystems created through human use of mineral resources, such as gravel pit lakes, can provide substitute habitats for conservation of freshwater and riparian biodiversity. However, many of these artificial ecosystems may exhibit high recreational use intensity, which may limit their biodiversity potential.The species richness of several taxa (plants, amphibians, dragonflies, damselflies, waterfowl, songbirds) was assessed and a range of taxonomic biodiversity metrics were compared between gravel pit lakes managed for recreational fisheries (N = 16) and unmanaged reference lakes (N = 10), while controlling for non-fishing related environmental variation.The average species richness of all examined taxa was similar among both lake types and no substantial differences in species composition were revealed when examining the pooled species inventory. Similarly, there were no differences among lake types in the presence of rare species and in the Simpson diversity index across all the taxa that were assessed.Variation in species richness among lakes was correlated with woody habitat, lake morphology (surface area and steepness) and land use, but not correlated with the presence of recreational fisheries. Thus, non-fishing related environmental variables had stronger effects on local species presence than recreational-fisheries management or the presence of recreational anglers.Collectively, no evidence was found that anglers and recreational-fisheries management constrain the development of aquatic and riparian biodiversity in gravel pit lakes in the study region. Conservation of species diversity at gravel pit lakes could benefit from an increasing reliance on habitat enhancement activities.Competing Interest StatementThe authors have declared no competing interest.View Full Text

ecology↗

bioRxiv2018

Impact of recreational fisheries management on fish biodiversity in gravel pit lakes with contrasts to unmanaged lakes

Gravel pit lakes constitute novel ecosystems that can be colonized by fishes through natural or anthropogenic pathways. Many of these man-made lakes are used by recreational anglers and experience regular fish stocking. Recreationally unmanaged gravel pits may also be affected by fish introductions, e.g., through illegal fish releases, thereby contributing to the formation of site-specific communities. Our objective was to compare the fish biodiversity in gravel pit lakes with and without the recent influence of recreational fisheries management. We sampled 23 small (< 20 ha) gravel pit lakes (16 managed and 7 unmanaged) in north-western Germany and compared fish community and diversity metrics obtained using littoral electrofishing and multimesh gillnet catch per unit effort data. Given the size of the lakes we sampled we expected species poor communities and elevated fish diversity in the managed systems due to stocking. The two lake types were primarily mesotrophic and did not differ in key abiotic and biotic environmental characteristics. Both lakes types hosted similar fish abundance and biomass, but were substantially different in terms of the fish community structure and species richness. Fish were present in all lakes with at least three species. We discovered a higher -diversity and a lower {beta}-diversity in managed gravel pit lakes compared to unmanaged lakes. Thus, recreational fisheries management appeared to foster homogenization of fish communities, likely because fisheries managers stock these lakes with desired fish species (e.g., piscivorous fishes and large bodied cyprinids). However, we also detected anthropogenic pathways in the colonization of unmanaged gravel pit lakes, presumably from illegal releases by private people. Importantly, hardly any non-native species were detected in the gravel pits we studied, suggesting that recreational fisheries management not necessarily promotes the spread of exotic species.\n\nSignificance StatementLittle is known about fish communities in artificially created gravel pit lakes. We compared those managed by recreational fishers with those lacking fisheries management in north-western Germany. We found fishes in all gravel pit lakes and demonstrated a higher -diversity but more homogenized fish communities in managed gravel pit lakes compared to unmanaged lakes. We did not detect the establishment of relevant abundances of non-natives fishes despite intensive fisheries management.

ecology↗