Discriminant analysis of principal components (DAPC) of American mink from Sweden grouped into 5 clusters (various colour) on the first two axes of DAPC.

<p>The main graph plots show the first two discriminant axes (explaining 47.7 and 27.8% of the variation respectively). Each point represents an individual, colour indicates the assignment of an individual to a cluster, whereas shape indicates the site of origin of an individual.</p

Distribution of all American mink samples and mink marked as migrants from the North Coast to Koster Islands (red circles) and from Koster Islands to the North Coast (brown circles).

<p>The migrants were assigned by two methods: STRUCTURE with q ≥ 0.8 (panel A), GeneClass2 with probability ≤ 0.03 (panel B). Numbers indicate the number of migrants at each location. Arrows indicate the direction of sea current. Background map: Europe Base Map—Level 1 Provinces, AND Products B.V. and AND Data Ireland Limited, ESRI.</p

Estimates of effective population size (<i>N</i>_e) derived with different measures for American mink samples collected in the years 2006–2011 in Sweden.

<p>LN–Linkage disequilibrium method, MC–Molecular coancestry method.</p

Results of hierarchical AMOVA comparing the genetic variation of American mink over 6 years within 3 sites in Sweden.

<p>Results of hierarchical AMOVA comparing the genetic variation of American mink over 6 years within 3 sites in Sweden.</p

Number of American mink removed from Koster Islands and the North Coast in consecutive culling seasons.

<p>Number of American mink removed from Koster Islands and the North Coast in consecutive culling seasons.</p

Maps showing the distribution of American mink samples in three study sites (Koster Islands, North Coast and South Coast) in Sweden.

<p>As in some locations more than one mink was culled, each point represents the location of at least one culled mink. Background map: Europe Base Map—Level 1 Provinces, AND Products B.V. and AND Data Ireland Limited, ESRI.</p

Bayesian assignment of American mink from Sweden in the genetic clusters identified by STRUCTURE analysed in two hierarchical levels.

<p>Each American mink is represented by a single vertical bar. The locality of origin and year of capture for each individual is indicated below. Dashed black lines indicate the threshold probabilities of 0.80 and 0.20, used to assign each individual to a single cluster. Red arrow indicates one individual from the South Coast which was caught in 2007 and was included with the group of mink caught in 2010. M–indicates individuals from Koster Island assigned as migrants from the coast at level 1.</p

The proportion of migrants and the number of males and females dispersed between sites.

<p>M–males; F–females. Information about sex was not available for all collected mink samples.</p

Characteristic of tree cavities in sal <i>Shorea robusta</i> forest, Nepal

<p>Tree cavities are one of the key structures that influence abundance and diversity of cavity-dependent organisms in forests. The natural processes that lead to cavity formation and regulate the abundance of cavities are poorly understood, especially in subtropical regions of Asia. Surveys of tree cavities suitable for breeding birds were conducted in southern Nepal in sal <i>Shorea robusta</i> dominated forest. A cavity was defined as a hole in a tree trunk or a limb with a minimum entrance diameter of 2 cm × 2 cm, interior space, depth at least 2 cm and a solid bottom with a minimum diameter of 5 cm. Within 50 sample plots, we found 104 tree cavities. The mean height of cavity entrances (6.8 m above the ground) varied across tree species from 3.4 m in <i>Dillenia pentagyna</i> to 10.3 m in <i>S</i>. <i>robusta</i>, and was positively correlated with DBH of tree. The entrance exposures were most often to the south (38.2%), and located mainly in trunks (74.0%). Cavity entrances were very different in size, with mean smallest diameter 7.7 cm, the average depth of the cavity was 25.7 cm. Mode of cavity production (excavated or non-excavated) was best predicted by a model including diameter of cavity tree (DBH), cavity height and their interaction. Single check of cavities showed signs of use by birds in 21% of them. Excavated cavities accounted for 27.9% of all cavities, indicating that role of woodpeckers as cavity providers might be of importance for secondary users in sal forest.</p