Life history patterns in female moose (Alces alces): the relationship between age, body size, fecundity and environmental conditions Export

@article{citeulike:6075891, abstract = {I examined the relationship between age, body size and fecundity in 833 female moose (Alces alces) from 14 populations in Sweden sampled during 1989–1992. Data on population density, food availability and climatic conditions were also collected for each population. Age and body mass were both significantly positively related to fecundity, measured as ovulation rate, among female moose. The relationship between the probability of ovulation and body mass was dependent on age with (1) a higher body mass needed in younger females for attaining a given fecundity, and (2) body mass having a stronger effect on fecundity in yearling (1.5 year) than in older (=2.5 year) females. Thus, a 40 kg increase in yearling body mass resulted in a 42\% increase in the probability of ovulation as compared to a 6\% increase in older females. The lower reproductive effort per unit body mass, and the relatively stronger association between fecundity and body mass in young female moose compared to older ones, is likely to primarily represent a mechanism that trades off early maturation against further growth, indicating a higher cost of reproduction in young animals. In addition to age and body mass, population identity explained a significant amount of the individual variation in fecundity, showing that the relationship between body mass and fecundity was variable among populations. This variation was in turn related to the environment, in terms of climatic conditions forcing female moose living in relatively harsh/more seasonal climatic conditions to attain a 22\% higher body mass to achive the same probability of multiple ovulation (twinning) as females living in climatically milder/less seasonal environments. The results suggests that the lower fecundity per unit body mass in female moose living in climatically harsh/more seasonal environments may be an adaptive response to lower rates of juvenile survival, compared to females experiencing relatively milder/less seasonal climatic conditions.}, author = {Sand, H\r{a}kan}, citeulike-article-id = {6075891}, citeulike-linkout-0 = {http://dx.doi.org/10.1007/BF00328601}, citeulike-linkout-1 = {http://www.springerlink.com/content/pm41v55342phn80j}, day = {1}, doi = {10.1007/BF00328601}, journal = {Oecologia}, keywords = {alces, fecundity, life-history, moose, reproduction, senescence}, month = {April}, number = {2}, pages = {212--220}, posted-at = {2009-11-05 18:14:02}, priority = {2}, title = {Life history patterns in female moose (Alces alces): the relationship between age, body size, fecundity and environmental conditions}, url = {http://dx.doi.org/10.1007/BF00328601}, volume = {106}, year = {1996} }

TY - JOUR ID - citeulike:6075891 L3 - citeulike-article-id:6075891 N2 - I examined the relationship between age, body size and fecundity in 833 female moose (Alces alces) from 14 populations in Sweden sampled during 1989–1992. Data on population density, food availability and climatic conditions were also collected for each population. Age and body mass were both significantly positively related to fecundity, measured as ovulation rate, among female moose. The relationship between the probability of ovulation and body mass was dependent on age with (1) a higher body mass needed in younger females for attaining a given fecundity, and (2) body mass having a stronger effect on fecundity in yearling (1.5 year) than in older (=2.5 year) females. Thus, a 40 kg increase in yearling body mass resulted in a 42% increase in the probability of ovulation as compared to a 6% increase in older females. The lower reproductive effort per unit body mass, and the relatively stronger association between fecundity and body mass in young female moose compared to older ones, is likely to primarily represent a mechanism that trades off early maturation against further growth, indicating a higher cost of reproduction in young animals. In addition to age and body mass, population identity explained a significant amount of the individual variation in fecundity, showing that the relationship between body mass and fecundity was variable among populations. This variation was in turn related to the environment, in terms of climatic conditions forcing female moose living in relatively harsh/more seasonal climatic conditions to attain a 22% higher body mass to achive the same probability of multiple ovulation (twinning) as females living in climatically milder/less seasonal environments. The results suggests that the lower fecundity per unit body mass in female moose living in climatically harsh/more seasonal environments may be an adaptive response to lower rates of juvenile survival, compared to females experiencing relatively milder/less seasonal climatic conditions. IS - 2 JF - Oecologia EP - 220 TI - Life history patterns in female moose (Alces alces): the relationship between age, body size, fecundity and environmental conditions VL - 106 SP - 212 KW - alces KW - fecundity KW - life-history KW - moose KW - reproduction KW - senescence AU - Sand, Håkan PY - 1996/04/01/ UR - http://dx.doi.org/10.1007/BF00328601 ER -