Biology subjects

Tryjanowski, P.

Publications and source records attributed to Tryjanowski, P..

3 recordsLinked to original sources

bioRxiv2023

Habitat amount, temperature and biotic interactions drive community structure, life-history traits, and performance traits of cavity-nesting bees and wasps and their natural enemies in cities

O_LIUrban ecosystems are associated with socio-ecological conditions that can filter and promote taxa. However, the strength of the effect of ecological filtering on biodiversity could vary among biotic and abiotic factors. Here, we investigate the effects of habitat amount, temperature, and host-enemy biotic interactions in shaping communities of cavity-nesting bees and wasps (CNBW) and their natural enemies. C_LIO_LIWe installed trap-nests in 80 sites distributed along urban intensity gradients in 5 European cities (Antwerp, Paris, Poznan, Tartu and Zurich). We quantified the species richness and abundance of CNBW hosts and their natural enemies, as well as two performance traits (survival and parasitism) and two life-history traits (sex ratio and number of offspring per nest for the hosts). We analysed the importance of the abiotic and biotic variables using generalized linear models and multi-model inference. C_LIO_LIWe found that habitat amount and temperature were the main drivers of CNBW host responses, with larger habitat amounts resulting in higher species richness and abundance, and a larger total number of brood cells per nest for both bees and wasps, as well as a larger probability of survival for bees. Conversely, higher local temperatures decreased species richness, abundance, survival rate, number of brood cells per nest, and proportion of females in CNBW hosts. C_LIO_LIBiotic interactions with natural enemies shaped wasp species richness, with higher levels of parasitism resulting in more wasp species. Similarly, our results showed direct density-dependence between CNBW hosts and their natural enemies. C_LIO_LIOverall, our study highlights the importance of habitat amount and temperature in shaping urban food webs, through direct effects on hosts responses and the subsequent consequences for their natural enemies. As cities prepare to tackle the future consequences of global change, strategies that make it possible to maintain available habitat and mitigate urban overheating emerge as a key urban adaptation for biodiversity conservation. C_LI

ecology↗

bioRxiv2022

Urban birds' flight responses were unaffected by the COVID-19 shutdowns

The coronavirus disease 2019 (COVID-19) pandemic dramatically altered human activities, and, during shutdowns. Here, we evaluated whether urban birds from five countries changed their tolerance towards humans during the COVID-19 shutdowns. We collected 6369 flight initiation distance estimates for 147 bird species and found that human numbers in parks (at a given hour, day, week or year - before and during the COVID-19 shutdowns) had a little effect on birds tolerance of approaching humans. Apart from the actual human numbers in the area (hourly scale), the effect of human activity at other temporal scales centered around zero. The results were similar across countries, for most species or when we restricted our analyses only to species sampled both before and during the COVID-19 shutdowns. As expected, the level of daily human presence in parks (measured by Google Mobility Reports) correlated negatively with the stringency of governmental restrictions (a weekly proxy for human presence) and was overall lower during COVID-19 shutdowns than during the post-shutdown year (2022). Our results highlight the resilience of birds to changes in human numbers on multiple temporal scales, the complexities of linking animal fear responses to human behavior, and the challenge of quantifying both simultaneously in situ.

animal behavior and cognition↗

bioRxiv2022

The Crimean population of the lesser grey shrike (Lanius minor) has low behavioural flexibility in its response to approaching humans

The ongoing growth of the human population will increase the rate of wildlife-human interactions. High levels of animal tolerance and flexible responses towards human presence seem to be among the key mechanisms behind successful wildlife-human coexistence, but this behaviour remains unexplored for most populations and species of animals. Here, we investigate the escape behaviour (measured as flight initiation distance) of the Crimean population of a charismatic and declining bird species, the lesser grey shrike (Lanius minor). We examined its relationship with starting distance of the approaching human, directness of that approach (direct or tangential), habitat type (rural or suburban), and height of the perch used by shrikes. We found that the starting distance was significantly associated with escape responses of shrikes to approaching humans. In contrast, we found no significant association between escape responses and directness of approach, habitat type, or height of perch. Our results indicate that the lesser grey shrike may exhibit low flexibility in their escape responses towards humans which may have implications for their conservation management. Our results also indicate that the widely used 30 metres threshold for minimum starting distance may be insufficient for rural populations, even of small passerines.

animal behavior and cognition↗