Winter behavior of Saimaa ringed seals: Non-overlapping core areas as indicators of avoidance in breeding females

Abstract

Climate change, together with increasing human activity, poses a threat to the breeding success of endangered landlocked ringed seals (Phoca hispida saimensis). In this study, we estimated the spatial ecology of Saimaa ringed seals during the breeding season in the ice-covered period of December-April. The telemetry data on tagged seals (n = 20), with a total of 25 separate tracking periods and birth lair locations (n = 59) of non-tagged seals, were studied to estimate the movement ecology and breeding density. The movements of the ringed seals were more restricted during the ice-covered season; the total home range size (average 7.4 km2) in winter was 13 times smaller than that in summer. Individual tagged seals occupied an average of 5 ± 3 SD subnivean haul outs (snow lairs or ice cavities), and the mean distance between the haul outs was 1.6 ± 1.1 SD km (range 0.2–5.9 km). Moreover, our data indicated that ringed seal females likely exhibited breeding time avoidance of each other’s core areas, which may indicate some degree of territoriality. This was supported by the findings that the core areas (mean 1.2 km2) of tagged adult females (n = 9), did not overlap with each other. Also data on non-tagged seals showed that females did not give birth to pups within the core area radius of other parturient females. This study, together with earlier findings on the home ranges of nursed pups and perinatal mortality rates, has implications into land usage planning in Lake Saimaa by highlighting the need of undisturbed area between seal lairs and anthropogenic disturbances.

Patterns of Microbiome Variation Among Infrapopulations of Permanent Bloodsucking Parasites

“…Thirty-four individual lice were sampled from 17 individual Saimaa ringed seals (Pusa hispida saimensis), which is an endemic endangered landlocked subspecies of the ringed seal living in freshwater Lake Saimaa in Finland (e.g., Nyman et al, 2014). Individual lice were collected from seals found dead or from seals that were live-captured for telemetry studies (e.g., Niemi et al, 2019), and placed in 2-ml screw-cap tubes with 99.5% ethanol. Lice from a single seal individual were put in the same tube.…”

Home range variation in leopards living across the human density gradient

“…1 Humans increasingly are affecting ecosystems worldwide, with well-known effects on biodiversity. Most of the focus on these impacts has been on biodiversity loss and ecosystem functioning (Koerner et al 2017), but there also is increasing evidence that even at the individual scale, animals are altering behavior in the face of these rapid and large-scale changes (Dumyahn and Pijanowski 2011;Niemi et al 2019). Disturbance by humans presumably worsens habitat quality for most species, causing changes in behavior (Parsons et al 2016).…”

A mark–recapture approach for estimating population size of the endangered ringed seal (Phoca hispida saimensis)

“…As a statistically significant transient effect was observed, this should be taken into account in future population models when surveying the whole Lake Saimaa basin since it has been pointed out that sub-adult seals may move to the edges of the breeding areas, which would support this transient effect [ 69 ]. This effect could be introduced into the Cormack–Jolly–Seber models and the estimation of survival in future studies, but it is not applicable to the POPAN model as used here (see [ 30 ]).…”