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Understanding population dynamics requires knowledge of the differential effects of survival, productivity and dispersal on population growth. This is particularly important for the conservation of small and recently established populations, where stochastic births and deaths may result in negative growth and even extinction. Here, we investigated the population dynamics of a small population of Eurasian cranes Grus grus in the UK and the effect of a population reinforcement in population growth. We also estimated the probability that the conservation status of cranes improves in the future. We developed stochastic population models to assess the population dynamics and the effect of adding 90 individuals between 2010 and 2014. The best‐supported models suggest that the crane population is self‐sustaining with an annual adult survival of 0.88, but suffers from low productivity. In addition, much of the population increase has been driven by immigration of birds from continental Europe. We found that population reinforcement resulted in a 50% increase in the projected population size, from 178 to 275 breeding pairs over the next 50 years. We showed that the relative contribution of immigration to population growth declined from 43%, when the translocated birds were not considered, to 29%, when they were included in the breeding pool. Moreover, after the population reinforcement, the probability of the population improving its conservation status increased from just above zero to 32%. In light of the recent increase in translocation programs worldwide, our study highlights the need to consider population dynamics to successfully predict the increase in population size when management strategies, such as reintroductions and reinforcements, are planned. Understanding population dynamics is particularly important for the conservation of small populations. We investigated the population dynamics of a small population of Eurasian cranes (Grus grus) in the UK and how a reinforcement program affected its population growth. Our models show that the crane population is self‐sustaining but suffers from low productivity, and that much of the population increase has been driven by immigration from continental Europe. Importantly, population reinforcement resulted in a 50% increase in the projected population size over the next 50 years. Overall, our study highlights the need to consider population dynamics to successfully predict population growth when reinforcements or reintroductions are planned. [ABSTRACT FROM AUTHOR]

Invertebrates dominate many terrestrial ecosystems in terms of biomass, and they also structure ecosystems through their roles as pollinators, detritivores, primary consumers, predators and prey. Invasive rodents (rats and mice) are known to have detrimental effects on many island invertebrates, although these effects are seldom quantified or ecologically understood. Here we provide evidence of the effects of invasive rats ( Rattus spp.) on island invertebrate populations using a large-scale natural experiment. We investigated the effects of invasive rats on Falkland camel crickets ( Parudenus spp.) in the Falkland Islands (South Atlantic) by comparing an index of camel cricket relative abundance between 18 rat-infested islands, six rat-eradicated islands and 13 naturally rat-free islands (in total, 37 islands). Our study provided two key results. First, camel crickets were up to an order of magnitude more abundant on rat-free islands than on rat-infested or rat-eradicated islands. This difference was larger in native tussac grass Poa flabellata than in other vegetation types. Second, camel cricket populations recovered after rat eradication, because the relative abundance of camel crickets on rat-eradicated islands was intermediate between those of naturally rat-free and rat-infested islands, and among rat-eradicated islands relative abundance was lowest where rats had been cleared most recently. Our results demonstrate severe suppression of a superabundant and large-bodied island endemic invertebrate by invasive rodents, and its prompt recovery after rodent eradication. [ABSTRACT FROM AUTHOR]

The author explores the writings of John Strecche, 15th century canon of the Augustinian priory of St. Mary in Kenilworth, Warwickshire, England. He focuses on Book Four, the "History of England," tracing its provenance, references, author's signatures, script style, and content. He also compares Strecche with other medieval chroniclers.

Measures to boost populations can help ensure population persistence in the short‐term while longer‐term conservation interventions take effect. Headstarting, involving the collection of wild early life‐stage individuals, rearing in captivity, and release into a new or existing population once independent, has recently been identified as a potential translocation technique to assist small breeding populations of waders declining due to low levels of productivity. However, the demographic rates of headstarted individuals have not been quantified, and their impact on target populations not understood, which is required to determine the efficacy of this technique as a tool for species recovery. Between 2017 and 2022, headstarting was trialled as a tool to supplement the critically small sub‐population of black‐tailed godwit (Limosa limosa limosa) breeding at the Ouse Washes, Eastern England. We demonstrate that a high survival rate for eggs and chicks can be achieved through artificial incubation and hand‐rearing, and that headstarting can substantially increase the overall productivity of a small population. Using survival analysis and mixed effects modelling, we show that apparent survival and breeding success of headstarted individuals is comparable to wild‐reared conspecifics. The survival rate of released birds was sufficient to significantly boost the breeding population, reaching over five times the number of breeding pairs at the release site during the trial. Providing demographic rates remain the same, the number of godwits breeding at the Ouse Washes is predicted to continue to increase moderately over the next 20 years. This study highlights the potential of headstarting to boost small populations of breeding waders, and demonstrates the value of this technique to assist with the recovery of threatened populations when there is a clear justification that headstarting can negate the effects of population limiting factors. [ABSTRACT FROM AUTHOR]

The article discusses the use of predictive models to understand and evaluate wildlife conservation. It mentions development of models that base predictions on fitness maximization decision-rules. it also mentions efforts of scientists and conservation practitioners to use tools to maximize conservation efforts.

Diurnal and nocturnal time-activity budgets were compiled for White-headed Ducks at their most important wintering area, Burdur Lake in Turkey, during February and March 1993. During the day, ducks spent 28% of the time feeding, 57% resting, 11% in locomotion, 4% preening and 1% in alert behaviour. No courtship behaviour was observed. Restingpeaked in the middle of the day. As wave-height increased, feeding and swimming increased and resting decreased. At night, 92% of time was spent feeding. Sites used by White-headed Ducks held a higher biomass of food items (benthic chironomid larvae) than other parts of the lake. Movement of individuals and marked differences in diurnal time budgets occurred between sites, as birds concentrated in flocks for resting and dispersed to feed. The proportion of birds resting increased with the number of birds present, both within and between sites. Feeding was concentrated at those sites supporting a higher biomass ofchironomids for a given depth. [ABSTRACT FROM AUTHOR]

Annual production of mast by the beech is highly variable, yet thereare few long-term records of the extent of masting which might help to explain the masting phenomenon. In this 16-year study, beech mast has been sampled from 100 trees by 7-min samples collected from the ground and from low-growing branches at sites ranging from the south to the north of England, and varying from closed canopy beechwood to shelter belts, avenues and isolated trees in parks. Variation in production of viable seed is much greater from year to year than from north to south. Good masting occurred in 1980, 1982, 1984, 1990 and 1995:in these years at least one year of very bad masting normally followed. Otherwise, prediction of masting is unreliable. No full mast was found in 1981. Overall there was very little full mast in five other years, but even in these years, some sites or some trees produced an appreciable amount. All trees produced empty pericarps as well as full mast, especially on lower or shaded branches. Isolated trees produced more empty pericarps than trees in groups; this is likely to result from a lack of cross pollination. It is concluded that ground sampling for a fixed period affords a rapid and effective method of assessing masting despite the factors intervening between mast shedding andcollection. [ABSTRACT FROM AUTHOR]

Lead poisoning, through the ingestion of spent lead gunshot, is an established cause of morbidity and mortality in waterbirds globally, but the thresholds at which blood levels begin to affect the physiology of birds in the wild are less well known. Here we determine the prevalence of lead exposure in whooper swans and, for the first time, identify the level of blood lead associated with initial reductions in body condition. Blood lead elevated above background levels (i.e. >20 μg dL(-1)) was found in 41.7% (125/300) of swans tested. Blood lead was significantly negatively associated with winter body condition when levels were ≥44 μg dL(-1) (27/260 = 10%). Our findings indicating that sub-lethal impacts of lead on body condition occur at the lower end of previously established clinical thresholds and that a relatively high proportion of individuals in this population may be affected, reaffirm the importance of reducing contamination of the environment with lead shot., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

When an imminent attack by a predator on a group of birds is signalled to non-detectors only by the departure of the detector, non-detectors may make time-wasting false-alarm flights in response to mistaken or non-predator-driven departures. The frequency of false-alarm flights might be reduced if group members assess the reason for single departures before responding. Immediate flights should only occur after multiple simultaneous departures, because these are only likely to be generated by an attack. The response delay between the detectors' departure and the next birds that respond should then be dependent on the number of detectors. On sparrowhawk attack, response delays in redshanks decreased significantly as detector number increased, controlling for raptor conspicuousness and proximity, and flock size and spacing. If response delay is modified because of risk dilution, it should increase with flock size and, consequently, the rate of alarm flights due to mistakes should decrease. However, response delay did not increase and flight frequency due to misidentification of non-raptors or non-predator-driven departures did not decrease with flock size. Significantly more feeding time was lost by birds in small flocks, suggesting that the dilution effect decreased the cost of each false-alarm flight rather than their frequency.