Reproductive characteristics in female Swedish moose (Alces alces), with emphasis on puberty, timing of oestrus, and mating

Abstract

BackgroundThe moose (Alces alces) is an intensively managed keystone species in Fennoscandia. Several aspects of reproduction in moose have not been fully elucidated, including puberty, timing of mating and oestrus, and the length of the oestrus period. These aspects are relevant for an adaptive management of moose with respect to harvest, population size, demography and environmental conditions. Therefore, an investigation of female moose reproduction was conducted during the moose-hunting period in southern Sweden from 2008 to 2011.ResultsA total of 250 reproductive organs and information on carcass weight and age was collected from four different hunting areas (provinces of Öland, Småland, Södermanland, and Västergötland) in southern Sweden. The results showed that puberty in female moose varied with carcass weight, age, and time of season. The period for oestrous/mating lasted from about mid September to the beginning of November.ConclusionsThe oestrus period (predominantly for heifers) is longer than previously reported and was not finished when the hunting period started. Sampling the uterine cervix to detect spermatozoa was a useful method to determine if mating had occurred. To avoid hunting of moose during oestrus, we suggest that the hunting period should be postponed by at least 14 days in southern Sweden.

Characteristics of spermatozoa and reproductive organs in relation to age and body weight in Swedish moose (Alces alces)

“…In the present study, the mean testes weight decreased over the time period studied, indicating that a decline in sperm production and quality also takes place in moose bulls, which in turn indicates that the peak rut is over by the time the hunting period commences. This is supported by the findings of the timing of oestrus in female moose, where most adult females show oestrus just prior to the start of the hunting period in moose in southern Sweden (Malmsten et al, 2014).…”

“…Reproductive season in terms of the oestrus period, from the end of September to the beginning of October has been reported in moose (Garel et al, 2009;Haagenrud and Markgren, 1974;Markgren, 1969;Monfort et al, 1993;Schwartz and Hundertmark, 1993). However, a recent Swedish study (Malmsten et al, 2014) showed that some young adults, (or old cows with low body weight) did not have their first oestrus of the season until the end of October/beginning of November. The results of the present study indicate that mating during the latter part of October or beginning of November (during a late first oestrus or a second oestrus) may result in lower conception rates due to lower sperm quality since we found that the PNS decreased over time.…”

“…Again, this indicates that the body weight is more important for a high PNS than age of the male. As a comparison, the time at which yearling females reach puberty is also related to body weight (Saether and Haagenrud, 1983), rather than age (Malmsten et al, 2014). Since weight at birth in moose is negatively associated with adult body weight (Solberg et al, 2004), the birth weight may affect puberty in both males and females.…”

Influence of hunting on movements of moose near roads

“…In Sweden, the moose rut overlapped with the hunting period (Malmsten et al ). We tested whether observed patterns in moose movement behavior are due to behavioral changes in moose during the rut or due to hunting disturbances.…”

“…For many deer species, the rut is in fall. During the rut, female deer are in estrus and male deer modify their behavior to maximize their chances for mating (Mysterud et al , Malmsten et al ). In some deer species (e.g., moose, Bubenik , Leblond et al ; Columbian black‐tailed deer [ Odocoileus hemionus columbianus ], Long et al ; white‐tailed deer, Foley et al ), males intensify their movement possibly searching areas more effectively to find suitable mating partners.…”