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We report the results of all readily available inventories of wintering bats in Vermont. Surveys at 23 hibernacula were compiled from the literature and unpublished data of numerous biologists and cavers. The earliest Vermont records date back to 1934. Only five hibernacula were systematically surveyed for more than 45 years. Despite data limitations, several trends have emerged. Since the 1930s, wintering populations of Myotis sodalis have dramatically declined; wintering populations of M. lucifugus have increased; and wintering populations of all other Vermont species (M. leibii, M. septentrionalis, Eptesicus fuscus, and Pipistrellus subflavus) have remained small.

I investigated how a tropical hummingbird, Amazilia saucerottei, determines whether or not to defend a patch of Combretum farinosum and when to begin and end defense. Energetic value of a patch and number of flowers were not correlated through the period of flowering. First-day nectar production per flower declined from 68.11 J in late January to 19.07 J in early March. Patches of defended C. farinosum had a greater maximum number of nectar-producing inflorescences than did undefended patches. The threshold minimum number of nectar-producing inflorescences for defense decreased from 35 to 20 late in the flowering period. Defense began while the number of inflorescences producing nectar was below the threshold, indicating that birds assessed the patch's future value. The energetic value of a defended patch was the same at the beginning and end of territoriality (approximately 36 kJ), but the average number of nectar-producing inflorescences was twice as great at the end as at the beginning (11.6 vs 5.6), suggesting that birds asessed the value of the patch by direct measurement of energy intake. Daytime rate of energy expenditure estimated from time budgets was 0.545 J/sec. Total daily energy requirement was 34.14 kJ/day.