Examination of age distribution, time of birth and survival in a brown hare population

Abstract

Our research goal was to examine the (1) age distribution, the (2) date of birth and the (3) survival rate of a brown hare population. Data were collected between 2014 and 2016 in an agricultural region of Hungary. We examined altogether 346 shot animals from the hunting bag.

(1) There was no statistical difference between the years 2014 and 2015 when examining the homogeny of the age distribution of the whole autumn population. At the same time, age distributions between 2015-2016 and 2014-2016 can be considered to be different. The age distribution by under one year old individuals in 2014-2015 and 2015-2016 were different, but it can be considered homogeneous between 2014 and 2016.

(2) Most of the young hares were born between March and July in all three consecutive years, in detail: III-IV. 22%, IV-VI. 27% and VI-VII. 16% (altogether 65%) of the whole offspring.

(3) The survival rate (l_x) of the whole population was 0,55 in T1 period, and 0,45 in T2 by under 1 year olds, while in the group of 1-2 years old or older, it was 0,79 in T1 and 0,81 in T2. Examining the survival rate of the two age groups, no significant difference can be seen during the examined periods. Examined by age groups and sex, the survival rate was 0,62 under 1 year old males in T1 period, while it was 0,37 in T2; furthermore by the age group of 1-2 years old and older the survival rate was 0,74 in T1, and 0,64 in T2. The survival among males were homogeneous in the two years. The survival of females by under 1 year olds was 0,49 in T1, while 0,54 in T2. By the age group of 1-2 years old and older, the survival rate was 0,81 in T1, and 0,91 in T2. The survival of females between the two years is homogeneous.