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We tested whether the intensity of hardwood midstory reduction causes commensurate improvements of herbaceous groundcover in fire-suppressed Pinus palustris (longleaf pine) sandhills. Using a complete randomized block design, we compared the effects of three hardwood reduction techniques (spring burning, application of the ULW ® form of the herbicide hexazinone, chainsaw felling/girdling) and a no-treatment control on plant species richness, and on life form and common species densities at Eglin Air Force Base, Florida, U.S.A., from 1995 to 1998. ULW ® and felling/girdling plots were burned for fuel reduction two years after initial treatment application. We also sampled the same variables in frequently-burned reference sandhills to establish targets for restoration. Spring burns achieved partial topkill of oaks (17.6-41.1% from 1995 to 1998) compared to reductions of 69.1-94% accomplished by ULW ® and of 93.2-67.8% by felling/girdling treatments. We predicted that plant species richness and densities of herbaceous groundcover life forms would increase according to the percent hardwood reductions. Predictions were not supported by treatment effects for species richness because positive responses to fire best explained increases in plant richness, whereas ULW ® effects accounted for the largest initial decreases. Legumes, non-legume forbs, and graminoids did not respond to treatments as predicted by the hypothesis. Again, positive responses to fire dominated the results, which was supported by greater herbaceous densities observed in reference plots. Overall, we found that the least effective and least expensive hardwood midstory reduction method, fire, resulted in the greatest groundcover improvements as measured by species richness and herbaceous groundcover plant densities.

The relative abundance of an ungulate community in hunted and non-hunted areas was studied in Calakmul, a tropical forest in southern Mexico that includes a 723,815 ha Biosphere Reserve where no hunting is allowed and communal lands where hunting activity does take place. Tapir, white-lipped peccary (WLP), collared peccary, two species of brocket deer and white-tailed deer were the focal species. Relative abundance of ungulates was obtained by counting tracks along transects in three hunted sites and in the southern core area of the Calakmul Biosphere Reserve, a enforced part of the protected area of 350,000 ha where no hunting has been-permitted since 1989. A total of 1708 ungulates tracks were obtained along 206.1 km (n = 90 transects) divided among the four sites. Relative abundance of the species was estimated from the track encounter rate (TER) calculated as the number of tracks per species encountered per km of transect. No significant differences in brocket deer and collared peccary TER was found among hunted and non-hunted areas. TER for WLP was significant higher in the non-hunted area, while TER for white-tailed deer and tapir was significant higher in hunted sites. Hunting activity affected the ungulate species in Calakmul differently. Brocket deer, white-tailed deer and collared peccary are more resistant species toward the hunting pressure than the WLP, who needs an immediate protection plan throughout Calakmul. Hunting areas are important habitat refuges for tapir populations and they should be protected in these areas.Resumen La abundancia relativa de seis especies de ungulados fue obtenida a trave´s de conteos de huellas a lo largo de transectos en tres sitios con cacerı´a y en la parte sur de la Reserva de la Biosfera de Calakmul, una a´rea de alrededor de 350,000 ha donde la cacerı´a ha sido prohibida desde 1989. Tapir, pecarı´de labios blancos, pecarı´de collar, dos especies de venados temazates y el venado cola blanca fueron las especies estudiadas. Un total de 1708 huellas de ungulados fueron obtenidos a lo largo de 206.1 km (90 transectos) divididos en los cuatro sitios. La abundancia relativa de las especies fue estimada por medio de la tasa de encuentro de huellas (TEH) calculado como el nu´mero de huellas encontradas por km de transecto recorrido. La TEH de los venados temazates y el pecarı´de collar fue similar entre las a´reas con cacerı´a y sin cacerı´a. La TEH para el pecarı´de labios blancos fue significativamente mayor en el a´rea sin cacerı´a, mientras que la TEH del venado cola blanca y el tapir fueron significativamente mayor en los sitios con cacerı´a. La actividad de cacerı´a afecta a las especies de ungulados diferente en la regio´n de Calakmul. Los venados temazates, el venado cola blanca y el pecarı´de collar esta´n resistiendo mejor la presio´n de cacerı´a que el pecarı´de labios blancos quien necesita un plan inmediato de proteccio´n en toda el a´rea. La evidencia sugiere que las a´reas con cacerı´a en este estudio son importantes para las poblaciones de tapir, y que se de...

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