A total of 48 eye globes were collected and analyzed to estimate ages of bowhead whales using the aspartic acid racemization technique. In this technique, age is estimated based on intrinsic changes in the D and L enantiomeric isomeric forms of aspartic acid in the eye lens nucleus. Age estimates were successful for 42 animals. Racemization rate (kAsp) for aspartic acid was based on data from earlier studies of humans and fin whales; the estimate used was 1.18 10-3/year. The D/L ratio at birth ((D/L)0) was estimated using animals less than or equal to 2 years of age (n = 8), since variability in the D/L measurements is large enough that differences among ages in this range are unmeasurable. The (D/L)0 estimate was 0.0285. Variance of the age estimates was obtained using the delta method. Based on these data, growth appears faster for females than males, and age at sexual maturity (age at length 12-13 m for males and 13-13.5 m for females) occurs at around 25 years of age. Growth slows markedly for both sexes at roughly 40-50 years of age. Four individuals (all males) exceed 100 years of age. Standard error increased with estimated age, but the age estimates had lower coefficients of variation for older animals. Recoveries of traditional whale-hunting tools from five recently harvested whales also suggest life-spans in excess of 100 years of age in some cases.
An ethnobotanical study in the Cumbres de Monterrey National Park (CMNP), Nuevo Leon, Mexico was conducted. In spite of the large area (1,773.7 km2), heterogeneous physiography, contrasting plant communities and high species diversity of the CMNP, very little was previously known about its useful plants. Based on 95 interviews with inhabitants of the region who were 35 years or older, we recorded ethnobotanical data of 240 species (comprising 170 genera and 69 botanical families), and 146 different uses. Most of the cited uses (98) were found to be medicinal ones.Background: An ethnobotanical study in the Cumbres de Monterrey National Park (CMNP), Nuevo Leon, Mexico was conducted. In spite of the large area (1,773.7 km 2 ), heterogeneous physiography, contrasting plant communities and high species diversity of the CMNP, very little was previously known about its useful plants. Based on 95 interviews with inhabitants of the region who were 35 years old or older, we recorded ethnobotanical data of 240 species (comprising 170 genera and 69 botanical families), and 146 different uses. Most of the cited uses (98) were found to be medicinal ones.
The population biology, habitat utilisation and diet of a small, isolated
population of long-nosed bandicoots (Perameles nasuta)
was studied over a 22-month period at North Head in Sydney Harbour National
Park, New South Wales. Reproductive output in this urban environment was high,
with a mean litter size of 2.3 and production of up to four litters per year.
The peak of reproductive activity was in late spring and early summer, with a
cessation of breeding in late autumn or early winter. The main causes of death
were identified as road trauma (58% – probably an overestimate
because of the ease of finding road deaths) and predation by cats and foxes
(37% – probably an underestimate because of the difficulty of
locating carcasses unless radio-collared). Bandicoots utilised all
macrohabitats (open grassed areas, heath, forest, swamp and scrub), but
extensively used open grassed areas for foraging. Males had larger home ranges
(4.4 ± 0.8 ha) than females (1.7 ± 0.2 ha). The largest home
ranges of males coincided with the peak of the breeding season
(September–November). Throughout the year
P. nasuta fed primarily on beetles, invertebrate larvae
and ants, but also on other invertebrates and on plant and fungal material.
Some vertebrate and human- derived material (birdseed, vegetable scraps,
plastic, twine) was also eaten. Although remarkably adaptable in its
reproductive and dietary strategies, this population of long-nosed bandicoots
is likely to follow other urban bandicoot populations toward extinction unless
there is active management to reduce the high rate of mortality from motor
vehicles and introduced predators.
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