We present results of an international collaboration to survey American lobster Homarus americanus Milne-Edwards, 1837 nurseries in Atlantic Canada and the northeast United States from 2007 to 2009 under a standardized protocol involving two sampling methods, diver-based suction sampling and passive collectors. We surveyed young-of-year and older juveniles at 191 sampling sites over 39 sampling areas considerably expanding the known depth range and geographic limits of benthic recruitment. Young-of-year densities were strongly correlated in space with the abundance of older juveniles, signifying consistently strong settlement in the Gulf of Maine, lower Bay of Fundy, southwestern Nova Scotia and southern Gulf of St. Lawrence, and relatively weak settlement in southern New England, eastern coastal Nova Scotia and Newfoundland, a pattern consistent with commercial lobster harvests. Passive collectors elucidated bathymetric patterns of young-of-year recruitment in oceanographically contrasting regions. Although we observed young-of-year lobsters as deep as 80 m, they were most abundant above the thermocline in summer-stratified regions, such as the western Gulf of Maine and southern New England, and depth-wise differences were less extreme in thermally mixed waters of the eastern Gulf of MaineÁFundy region, a finding consistent with previous observations that postlarvae concentrate above the thermocline. Between the two samplers, we detected no sampling bias for young-of-year lobsters, although collectors may slightly underrepresent older juveniles entering from the surrounding sea bed. Finally, we found that interactions between juvenile lobsters and suspected predators or competitors in collectors, such as crabs and fishes, are weak and unlikely to bias collector results.

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\g=D\5-androstenediol (\g=D\5-diol) while having minimal androgenic activity is of potential biological importance because it binds to oestrogen receptors and has oestrogenic activity in several systems. We have examined \g=D\5-diol metabolism in post-menopausal women utilizing the constant infusion technique. The metabolic clearance rate for 11 subjects was 763 \m=+-\50 1/24 h or 467 \ m=+-\30 1/m2/24 h. Labelled dehydroepiandrosterone, testosterone, \g=D\4-androstenedione, androsterone and the sulphates of \g=D\5-diol, dehydroepiandrosterone and androsterone were found in the plasma. Of all the kinetic parameters only the conversion ratio for dehydroepiandrosterone sulphate was different from that for young women (4.958 \ m=+-\ 0.410 for young women vs 3.084 \m=+-\0.220 for older women). The plasma concentration of \g=D\5-diol was 0.94 \m=+-\0.19 ng/ml and the calculated blood production rate was 686 \m=+-\80 \g=m\g/24 h. The per cent free plasma \g=D\5-diol was 4.6 \m=+-\0.25. These values are slightly lower but not significantly different from those previously reported for normal young women.A5-androstene-3ß, 17ß-diol (A5-diol) has been con¬ sidered to be more important in the male than in the female having been shown to be an important intermediate in the biosynthesis of testosterone by human testicular tissue (Yanaihara & Troen 1972a,b). N More recently, there have been several reports suggesting that A5-diol combines with oestradiol receptors in several target tissues -rat uterus (Adams et al. 1978), rat mammary tumours (Adams et al. 1978; Nicholson et al. 1978) and MCF-7 mammary tumour cells (Kreitmann & Bayard 1979); this would suggest that A5-diol has potential oestrogenic properties. A5-diol is derived in part from circulating dehydroepiandrosterone (DHEA) and its sulphate (DHEAS) in women (Andriesse et al. 1978). We have previously reported on the kinetics of its metabolism in normal young men and women (Bird et al. 1976). Kirschner et al. (1973) have measured the metabolic clearance rates and pro¬ duction rates of A5-diol in normal and hirsute women. Because of our interest in the possible role of A5-diol in the endocrinology of breast cancer our first step was to examine the kinetics of A5-diol metabolism in normal post-menopausal women and to compare the results to those obtained in normal pre-menopausal women. We deemed this necessary because of the known changes of steroid hormone metabolism with age for some com¬ pounds but not for others. Materials and Methods SubjectsEleven normal women (ages 50-71 years) were studied.All were at least 5 year post-menopausal and were on no endocrine therapy. Their weights ranged from 50.7 to 88.1 kg. All were fully informed volunteers and had signed a consent form approved by an Ethics Review Committee.

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