Search results for "prey"
showing 10 items of 117 documents
Effect of preys and pollens on various biological parameters of the generalist Cydnodromus californicus (McGregor) (Parasitiformes, Phytoseiidae)
2008
Are habitat loss, predation risk and climate related to the drastic decline in a Siberian flying squirrel population? A 15 year study
2014
To devise effective conservation actions, it is important to know which factors are associated with the population parameters of a declining population. Using mark–recapture methods, we estimated the annual population size, growth rate and survival probability of an ear-tagged flying squirrel population over a 15-year period in a 4,500 ha study area in western Finland. The species is considered vulnerable, but detailed knowledge concerning population sizes or trends is lacking. The population parameters and changes therein were regressed against habitat availability, an indicator of predation pressure, and mean winter temperature (an indicator of climate change), to reveal potential reasons…
The effect of prey resources on evolutionary and ecological dynamics of prey (Serratia marcescens) and predator (Tetrahymena thermophila)
2006
Hard to catch: Experimental evidence supports evasive mimicry
2021
Most research on aposematism has focused on chemically defended prey, but the signalling difficulty of capture remains poorly explored. Similar to classical Batesian and Müllerian mimicry related to distastefulness, such ‘evasive aposematism' may also lead to convergence in warning colours, known as evasive mimicry. A prime candidate group for evasive mimicry areAdelphabutterflies, which are agile insects and show remarkable colour pattern convergence. We tested the ability of naive blue tits to learn to avoid and generalizeAdelphawing patterns associated with the difficulty of capture and compared their response to that of birds that learned to associate the same wing patterns with distast…
Impacts of reduced Lepidurus arcticus availability on brown trout life history traits in a mountain reservoir
2020
Lepidurus arcticus (the Arctic tadpole shrimp) is a vulnerable keystone species in Arctic and alpine water bodies where its occurrence and population size may influence the viability and life history traits of resident salmonids. Using data from a Norwegian mountain hydropower reservoir, Aursjoen, we illustrate how reduced availability of L. arcticus as prey resulted in the reduced condition, growth and delayed maturation of resident brown trout (Salmo trutta). We further link changes in the relative abundance of L. arcticus as prey to changing reservoir conditions, e.g. water level changes in the spring period, thereby establishing an indirect link between reservoir operation regimes and b…
Selection of spawning substratum by European river lampreys (Lampetra fluviatilis) in experimental tanks
2014
The selection of spawning substratum by the river lamprey (Lampetra fluviatilis) was studied in two experimental tanks with different flow conditions. In both tanks, four gravel sizes mixed with 15% sand were available to the test animals. In the tank with the lower current speed, lampreys selected in favour of the finest (2–8 mm) gravel size available against gravel sizes 4–20 mm and 8–40 mm. Selection was also significantly different in the tank with higher current speed where selection against the medium-sized substratum (4–20 mm) was evident, but there were no differences between selection for gravel sizes 2–8 mm, 2–40 mm and 8–40 mm relative to availability. Substratum selection and ob…
Migratory behaviour and holding habitats of adult river lampreys (Lampetra fluviatilis) in two Finnish rivers
2015
The effect of environmental factors on migratory activity of adult river lampreys entering the Kalajoki and Perhonjoki, rivers in Finland, for spawning was studied using correlation and regression analyses. Telemetric tracking of 60 individuals was utilized to study the migratory patterns and holding habitat requirements of adult river lampreys. The increases in the river discharge, wind forcing towards the river mouth and speed and magnitude of river water cooling had positive effects on the numbers of lampreys entering the rivers whereas the increase in the illumination intensity of the moon had a negative effect on their migration activity. Radio-tagged lampreys typically passed slow-flo…
Lotic life stages of the European river lamprey (Lampetra fluviatilis) : anthropogenic detriment and rehabilitation
2015
Olfactory cues and the value of information : Voles interpret cues differently based on recent predator encounters
2018
Prey strategically respond to the risk of predation by varying their behavior while balancing the tradeoffs of food and safety. We present here an experiment that tests the way the same indirect cues of predation risk are interpreted by bank voles, Myodes glareolus, as the game changes through exposure to a caged weasel. Using optimal patch use, we asked wild-caught voles to rank the risk they perceived. We measured their response to olfactory cues in the form of weasel bedding, a sham control in the form of rabbit bedding, and an odor-free control. We repeated the interviews in a chronological order to test the change in response, i.e., the changes in the value of the information. We found…
Research data supporting "Social learning within and across predator species reduces attacks on novel aposematic prey"
2019
This data is from the experiment that investigated how wild-caught blue tits and great tits use conspecific and heterospecific information about unpalatable prey, published at the Journal of Animal Ecology (2020). The experiment was conducted at the Konnevesi Research Station from October to December 2017. Sheet 1 (“Main experiment”) contains data from the main avoidance learning experiment. Sheets 2 (“Symbol preference blue tits”) and 3 ("Symbol visibility blue tits") contain data of blue tits' symbol choices in initial preference and visibility tests.