Isochrony in barks of Cape fur seal () pups and adults.

Animal vocal communication often relies on call sequences. The temporal patterns of such sequences can be adjusted to other callers, follow complex rhythmic structures or exhibit a metronome-like pattern (i.e.

Adoption and feeding of fieldfare nestlings and fledglings by European blackbird.

Interspecific adoption is an intriguing topic in behavioral and evolutionary ecology. As it is a rare phenomenon, seldom documented in the literature, reports of interspecific adoption based on solid data are particularly valuable. A long-term and extensive monitoring programme involving a local population of European blackbirds (, hereafter blackbird) has yielded, among other things, observations of alloparental behavior exhibited by blackbirds toward fieldfare () nestlings (a single nest, the first-ever record) and fledglings (12 cases in all).

Museum specimens of a landlocked pinniped reveal recent loss of genetic diversity and unexpected population connections.

The Saimaa ringed seal () is endemic to Lake Saimaa in Finland. The subspecies is thought to have originated when parts of the ringed seal population of the Baltic region were trapped in lakes emerging due to postglacial bedrock rebound around 9000 years ago. During the 20th century, the population experienced a drastic human-induced bottleneck.

Environmental niche overlap in sibling planktonic species and in Arctic fjords.

Knowledge of environmental preferences of the key planktonic species, such as copepods in the Arctic, is crucial to understand ecosystem function and its future under climate change. Here, we assessed the environmental conditions influencing the development stages of Atlantic and Arctic , and we quantified the extent to which their niches overlap by incorporating multiple environmental data. We based our analysis on a 3-year seasonal collection of zooplankton by sediment traps, located on moorings in two contrasting Svalbard fjords: the Arctic Rijpfjorden and the Atlantic-influenced Kongsfjorden.

Comparison of behavioural tendencies between "dangerous dogs" and other domestic dog breeds - Evolutionary context and practical implications.

Aggressive behaviour by dogs is a considerable social problem, but the ability to predict which individuals may have increased aggressive tendencies is very limited, restricting the development of efficient preventive measures. There is a common perception that certain breeds are more likely to exhibit aggressive behaviour, which has contributed to the introduction of breed-specific legislation. The rationale for such legislation explicitly assumes high heritability of this trait while also implying relatively little variation within breeds; these assumptions are largely untested.

Changes in the Montagu's Harrier Circus pygargus diet in Eastern Poland across decades promote insects and reptilians, but not birds and rodents.

We investigated temporal changes in diet composition of the Montagu's Harrier breeding in natural habitat (calcareous peat bog) in SE Poland. We characterized diet composition in a three-year period (2007-2009), based on pellet analyses. We investigated whether diet composition was affected by years or stage of breeding.

How environmental stressors affect reproductive potential in a saltmarsh plant species .

We examined whether the presence or absence of different environmental stressors influenced the reproductive potential of a saltmarsh species-. We focused on total seed output, seed quality, and biomass of progeny. So far, there are no studies trying to answer the question of how different saltmarsh management affects the quality of seed in saltmarsh species.

Intercolony variation in foraging flight characteristics of black-headed gulls during the incubation period.

Using GPS loggers, we examined the influence of colony, sex, and bird identity on foraging flight characteristics of black-headed gulls during the incubation period. We studied tracks of 36 individuals breeding in one urban and two rural colonies in Poland. Birds from both rural colonies performed the furthest flights (mean max distance 8-12 km, up to 27 km) foraging mainly in agricultural areas.