Biology_of_Mustelids_Vol_1.pdf

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here by the special features of the habitat of the martens, and also the
time and methods of hunting.
Bearing in mind the fact that martens become sexually mature only
in the second or even third year of life, and bear progeny only in the third
or fourth year, it becomes obvious that only some 20 per cent of the females
take part in the natural production of this valuable furred animal.
It
should also be noted that in natural conditions the number of progeny of
martens is usually small, with on average two or three young per litter.
This possibly is one of the causes of the observed decline in the
population of martens in the Republic, despite the increase in their stock
each breeding season.
Therefore, it appears necessary to modify the
methods of hunting, and to capture martens alive, in order to release the
females and also the males with the best fur qualities.
Summary
1 • Martens inhabiting the Republic have been subdivided by craniological
characters into three age groups:
the first under one year, the
second from one to three years and the third over three years.
2. The most characteristic signs reflecting the process of growth of
martens ~re
the changes in the structure of the occipital and sagittal
crests, the changes in the relative ratio of the interorbital and postorbital
constrictions, the changes in the length and width of the skull,
the degree of coalescence of the nasal bones, and,
to a lesser extent,
the degree of wear on the teeth.
3. In determining the age of the males the development of the
baculum is helpful•.
4. In natural conditions in the Republic, martens of the first age
group predominate (45.3%), second place is taken by individuals of the
second age group (28.6%), the third age group being the smallest (26.1%).
5. In view of the reduction in the rate of natural reproduction of
martens, it is recommended that they be caught alive and the breeding stock
conserved.