Voles include the prairie vole, woodland vole and the meadow vole. Other mammals found in Greater London are hedgehogs, rats, mice, rabbit, shrew, vole, and squirrels. The European Otter has been known to actively attack mink preying upon water vole. Patterns of mortality apparently vary among meadow vole populations. Many species of wading birds and water vole inhabit the loch shore. Among smaller animals, marmots, hares, and several types of pika and vole are common. Predator numbers are positively associated with meadow vole abundance. The bank vole is primarily a herbivore. The European snow vole is a relict species. Square habitat patches were not significantly different from rectangular patches in meadow vole density. The prairie vole is monogamous and forms a lifelong pair bond. The woodland vole is also usually monogamous. The average life of the smaller vole species is three to six months. There are approximately 155 different vole species. The character sings a number of Michel Sardou songs, most notably "Je vole".