Working Group on Marine Mammal Ecology (WGMME)

162 pages.-- This work is licensed under the Creative Commons Attribution 4.0 International Licence (CC BY 4.0)The Working Group on Marine Mammal Ecology met in 2021 to address new information on marine mammal ecology relevant to management. Two terms of references were standing ToRs; under the first of these, ToR A, new and updated information on seal and cetacean population abundance, population/stock structure, manage-ment frameworks as well as anthropogenic threats to individual health and population status were reviewed along with findings on threats to marine mammals such as bycatch, pollution, marine debris and noise. ToR B is a cooperation with WGBIODIV to review species-specific for-aging distributions (considering horizontal and vertical dimensions depending on data availa-bility) and to estimate consumption by marine mammal species representative in case study ar-eas. ToR C was implemented to review aspects of marine mammal fishery interactions not cov-ered by ICES WGBYC. ToR D is the second standing ToR and concerns updating the WGMME seal database, which was updated with the latest dataN

Working Group on Marine Mammal Ecology (WGMME)

159 pages.-- This work is licensed under the Creative Commons Attribution 4.0 International License (CC BY 4.0)The Working Group on Marine Mammal Ecology met in 2022 to address five terms of reference. Under the first of these, ToR A, new information on cetacean and seal population abundance, distribution, population/stock structure, was reviewed, including information on vagrant ma-rine mammal species. This was done to ensure the recording of possible range changes in marine mammal species in the future. For cetaceans, an update is given for the different species, providing for a latest estimate for all species studies. In this report, particular attention is given to the updating of information from Canadian and US waters, and together with those countries, latest estimates for cetacean species are provided. For seals, latest monitoring results are given for harbour, grey and Baltic ringed seals. In addition, where possible, local long-term trends are illustrated for those species, based on earlier WGMME efforts to assemble these data into the WGMME seal database. For both spe-cies’ groups, a first account of vagrant species is providedN

Metabolism of estrone sulfate by normal breast tissue : Influence of menopausal status and oral contraceptives

The metabolism of [ 3 H]estrone sulfate ([ 3 H]E 1 S) was studied in normal breast tissue from 10 premenopausal women without oral contraceptives (OC), in 12 OC users and in 9 untreated postmenopausal women. [ 3 H]E 1 S was converted into estrone ([ 3 H]E 1 ) and estradiol-17β ([ 3 H]E 2 ) by tissue samples from all three groups of women, with only minor formation of other unconjugated compounds. The rate of [ 3 H]E 2 formation was significantly higher in premenopausal women without OC than in postmenopausal women. Among premenopausal women, OC users had a significantly lower rate of total hydrolysis and of [ 3 H]E 1 formation than non-users. The rate of total hydrolysis of [ 3 H]E 1 S in normal breast tissue from all three groups of women was similar to that in muscle, but the rate of [ 3 H]E 2 formation was ten times higher. Both total hydrolysis rate and rate of [ 3 H]E 2 formation were significantly lower in normal breast tissue than in breast carcinoma and in normal and neoplastic endometrium. The specific ability of normal breast tissue to convert E 1 S into the terminal biologically active estrogen E 2 may be important for estrogenic stimulation of the breast in subjects with low circulating E 2 levels. The lower rate of E 1 formation in OC users may reflect an inhibitory effect of the progestagen compound in such preparations

Effects of oral contraceptives on body composition and physical performance in female athletes.

Menstrual disturbances are common among female athletes, and oral contraceptives (OCs) are often recommended as estrogen substitution. However, there is little information about the effects of OC use in athletes, and there is great concern that OCs might impair physical performance. The aim of this study was to investigate the effects of OC use on body composition and physical performance in female athletes. Twenty-six endurance athletes (13 with oligo-/amenorrhea and 13 regularly menstruating athletes) and 12 sedentary controls were examined before and after 10 months of treatment with a low dose, monophasic, combined OC. Significant changes in body composition were recorded in the athletes, but not in the controls. There was an increase in weight and fat mass only in athletes with oligo-/amenorrhea. These changes were associated with a decrease in ovarian androgens. OC treatment also increased bone mineral density, with the largest increase in athletes with a low bone mineral density at baseline. Despite significant changes in body composition, little impact on physical performance was recorded. We have demonstrated that OC treatment in female athletes has predominantly beneficial effects on body composition without adverse effects on physical performance and could be used for the prevention of osteoporosis in athletic amenorrhea. However, it cannot be excluded that a marked increase in fat mass might have unfavorable effects for athletic performance in individual women