Lay SummaryInvasive rose-ringed parakeets caused behavioral changes in native garden birds that reduced their feeding rates. Understanding how invasive species impact native species can be complex, especially in urban environments where many other factors are also at play. We therefore used an experiment to disentangle these factors and demonstrate that parakeets are more disruptive than a dominant native competitor.

1. The release of more than 40 million captive-bred pheasants and red-legged partridges in Britain annually represents a significant addition to the potential food resource base for predators and scavengers. If this extra food availability subsidizes predator populations, gamebird releases could increase predation pressure on other wild birds, affecting their populations.2. Using three extensive datasets, we examined the spatial relationships between reared and free-roaming gamebirds (pheasant Phasianus colchicus and red-legged partridge Alectoris rufa), and explored spatial and temporal associations between these gamebirds and five species of avian predator (buzzard Buteo buteo, jay Garrulus glandarius, raven Corvus corax, magpie Pica pica and hooded Corvus cornix and carrion Corvus corone crows combined) in lowland rural Britain. 3. Patterns of spatial variation in the abundance of free-roaming gamebirds across Britain appear to be largely determined by gamebird releases, over and above any effects of land use or habitat. Predominantly positive associations between gamebird abundance (both reared and free-roaming) and the abundance and inter-annual population growth rates of predators tested suggest that large-scale variation in avian predator populations may be positively affected by gamebird releases. 4. Synthesis and applications. The positive associations between large-scale gamebird release and predator populations shown here may have implications for prey populations if the releases cause increased predation pressure. If this occurs, game management could have an indirect negative impact on some prey species partially counteracting previously reported positive or benign effects of game management on wider biodiversity. Overall impacts of gamebird releases are likely to be determined by complex interactions between multiple factors, including induced predation pressure, better understanding of which would be possible with compulsory recording of releases and numbers of predators killed. Restriction of releases warrants further investigation and consideration as a potential conservation tool for wild bird populations. K E Y W O R D S corvids, game management, pheasant, predation, raptors, rear and release, red-legged partridge | 2103 Journal of Applied Ecology PRINGLE Et aL.

Aim Hotspots of human activity are focal points for ecosystem disturbance and non‐native introduction, from which invading populations disperse and spread. As such, connectivity to locations used by humans may influence the likelihood of invasion. Moreover, connectivity in freshwater ecosystems may follow the hydrological network. Here we tested whether multiple forms of connectivity to human recreational activities promotes biological invasion of freshwater ecosystems. Location England, UK. Time period 1990–2018. Major taxa studied One hundred and twenty‐six non‐native freshwater birds, crustaceans, fish, molluscs and plants. Methods Machine learning was used to predict spatial gradients in human recreation and two high risk activities for invasion (fishing and water sports). Connectivity indices were developed for each activity, in which human influence decayed from activity hotspots according to Euclidean distance (spatial connectivity) or hydrological network distance (downstream, upstream and along‐channel connectivity). Generalized linear mixed models identified the connectivity type most associated to invasive species richness of each group, while controlling for other anthropogenic and environmental drivers. Results Connectivity to humans generally had stronger positive effects on invasion than all other drivers except recording effort. Recreation had stronger influence than urban land cover, and for most groups high risk activities had stronger effects than general recreation. Downstream human connectivity was most important for invasion by most of the groups, potentially reflecting predominantly hydrological dispersal. An exception was birds, for which spatial connectivity was most important, possibly because of overland dispersal capacity. Main conclusions These findings support the hypothesis that freshwater invasion is partly determined by an interaction between human activity and species dispersal in the hydrological network. By comparing alternative connectivity types for different human activities, our approach could enable robust inference of specific pathways and spread mechanisms associated with particular taxa. This would provide evidence to support better prioritization of surveillance and management for invasive non‐native species.

Anthropogenic pressure has well-documented effects on the spatial distribution of biodiversity but it can also have more subtle effects on wildlife, influencing the time of the day and for how long animals are active. These temporal effects have not received much attention from the scientific and conservation community, despite activity being intrinsically related to crucial aspects in an animal's life. Here we use data from a large-scale camera trap survey (517 survey sites covering more than 1000 km 2 ) conducted in areas under distinct levels of protection in the Brazilian Cerrado to investigate the effect of anthropogenic pressure on the activity of mammal species >1 kg. We used both circular statistics and GLMMs to investigate whether species would shift activity towards the night in response to disturbance, resulting in a decrease of diurnal activity in areas under lower protection levels and closer to households. Our results revealed that most species investigated did not show a temporal response to anthropogenic pressure, with only two species responding in the way we expected: tamanduas reduced the probability of daytime activity closer to households and collared peccaries reduced diurnal activity slightly in areas under lower protection levels. Our findings also suggest that environmental factors have a greater influence on species' activity than indicators of pressure in the mosaic of protected areas studied. Although stricter levels of habitat protection are known to have a positive and strong influence on the spatial distribution of many mammal species in the study region, we showed here that human pressure has only a modest effect on the period these species were active. This limited temporal response highlights the need for large natural areas under low disturbance that allow mammal species to respond spatially to threats.

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