Sentences with phrase «nest predation rates»
In addition, overlap in use of nest sites with coexisting species may increase nest predation rates [21].
https://bmcevolbiol.biomedcentral.com/ Not exact matches
But predation, even with bears included, didn't explain elk's low pregnancy rates.
«This is the first illustration that the spiders could also use the chemical cues to try to decrease the predation rate and also increase the attraction of prey,» says I - Min Tso of Tunghai University in Taiwan, who wasn't involved in the study.
He found higher rates of nest predation in small woodlots near human communities because these areas had higher populations of raccoons (Procyon lotor) and squirrels (Sciurus spp.) and few, if any, large predators, such as cougars and bobcats (Lynx rufus).
``... the ecological and conservation significance of these kill tallies is difficult to contextualise, because (1) there are no reliable estimates of the total population of birds in Australia; (2) predation may fall disproportionately on some bird species; (3) some bird species may be able to sustain high mortality rates and maintain viable populations but others may not; and (4) as demonstrated here, there is substantial spatial variation in the numbers and proportion of birds killed across Australia.»
The two studies can not be compared directly for a number of reasons, but by way of comparison, the average predation rate used by Lepczyk et al. is approximately 31 birds / cat for the 22 - week breeding season.
In it, she touches on all the usual talking points (e.g., cats are non-native, exaggerated predation rates, etc.), and portrays her trapping as a civic duty — done in the best interest not only of the community, but also of the cats.
Summarizing a recent study of gray catbird fledglings in the Washington, DC area, the SMBC claims that cats were responsible for «alarmingly high rates of nest predation and fledging [sic] mortality.»
But, as I've pointed out repeatedly, even high rates of predation do not equate to population declines (though, clearly, it's easy to suggest as much).
First, as was mentioned previously, even high rates of predation do not equate to population declines.
After excluding studies that did not meet a priori inclusion criteria designed to increase the accuracy of our analysis, we developed probability distributions of predation rates on birds and mammals.
where npc is the number of owned cats in the contiguous United States, pod is the proportion of owned cats granted outdoor access, pph is the proportion of outdoor owned cats that hunt wildlife, ppr is the annual predation rate by owned cats, cor is a correction factor to account for owned cats not returning all prey to owners, nfc is the number of un-owned cats in the contiguous United States, pfh is the proportion of un-owned cats that hunt wildlife, and fpr is the annual predation rate by un-owned cats.
As not all cats were studied in all seasons due to differences in the timing of recruitment, pet mortality and volunteer drop - out, predation rates were calculated seasonally to maximize sample sizes.
Research conducted in more densely populated areas, or areas where unowned cats aren't entirely reliant on prey for their meals, reveals predation rates far lower than 80 percent, [12] especially for birds.