The History of Elk (Cervus canadensis) Restoration in Ontario

Elk (Cervus canadensis) historically inhabited southern Quebec and central Ontario, but, by the early 1900s, the species was extirpated from this region. Attempts to re-establish an Elk population in Ontario during the first half of the 20th century had limited success. We reviewed historical documents, population census records, and a previous study pertaining to Elk reintroduced to Ontario in the early 1900s for clues to the cause(s) of their limited population growth. After an apparent rapid population increase in the 1940s followed by unregulated hunting during the subsequent 3 decades, Elk abundance in Ontario had not appreciably changed from 1970 to 1997, most likely because of the small founding population, unsustainable hunting, and accidental mortality. After the abolition of legal hunting in 1980, natural mortality appeared to be the main limiting factor. A limited sample of pregnancy and calf recruitment rates, body measurements, and physical condition parameters collected in 1993–1997, suggested that adults were healthy, reproducing successfully, and not limited by food availability; thus, it was concluded that remnant Elk populations could be augmented by introducing additional animals. A renewed Elk restoration effort, conducted from 1998 to 2001, imported 443 Elk from Elk Island national Park in Alberta to 4 release areas across central Ontario (Lake of the Woods, Lake Huron North Shore, Nipissing/French River, and Bancroft/North Hastings), resulting in a provincial population of about 800 Elk by 2013.

Response of understory vegetation of Adirondack forests to nitrogen additions

The influence of N pulses in the form of experimental additions of HNO3 at two times ambient and (NH4)2SO4 at two and four times ambient on the herbaceous and woody understory plants in three Adirondack Mountain hardwood forests was evaluated. Addition of (NH4)2SO4 decreased cover of dominant herbs and woody seedlings at Woods Lake, a site in the western Adirondacks. Tissue N concentrations of combined herbs and ferns at Woods Lake increased with addition of roman NH sub 4 sup + at both levels (9% at two times ambient; 13% at four times ambient) and increased with all three N treatments at Huntington Forest, a central Adirondack site (14% with roman NO sub 3 sup - and roman NH sub 4 sup + at two times ambient; 22% with roman NH sub 4 sup + at four times ambient). Seedlings of American beech (Fagus grandifolia Ehrh.) increased foliar N concentration 7-8% with addition of roman NH sub 4 sup + treatments at Huntington Forest, but did not respond to N addition at Woods Lake and Pancake Hall Creek, a western Adirondack site. In general, greatest plant nutrient response to N addition occurred at Huntington Forest, where atmospheric inputs of N are lower than at Woods Lake and Pancake Hall Creek.

Effects of base addition and brook trout (Salvelinus fontinalis) introduction on the plankton community of an acidic Adirondack lake

Calcite was added to Woods Lake in 1985 and 1987, and to its watershed in 1990, to restore and maintain water quality conditions suitable for reestablishing brook trout (Salvelinus fontinalis). Juvenile and adult brook trout were introduced following the first chemical treatment and were stocked annually thereafter from 1985 to 1989. In response to the combined chemical and biological manipulation, phytoplankton abundance increased whereas production per unit of biomass decreased. We attribute the increase in phytoplankton abundance and the reduction in biomass turnover rates to a decrease in zooplankton grazing. Zooplankton densities and estimated community grazing rates were lower during the posttreatment period despite a shift from small-bodied taxa (Diaptomus minutus, Bosmina longirostris) to a more diverse assemblage that included four species of daphnids. We attribute reductions in zooplankton abundance to planktivory of introduced brook trout. The changes we observed in phytoplankton and zooplankton species composition were consistent with trends observed during whole-lake acidification experiments, but functional responses in our experiment (decreased zooplankton abundance, increased phytoplankton abundance) were not. Our functional responses were consistent, however, with those observed previously in food webs manipulated to increase planktivore abundance.