Landscapes Forest and Global Change - ESA - Escola Superior ...

L.R.P. Williamson et al. 2010. Anthropogenic landscape changes and the conservation of woodland caribou
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season (Culling et al. 2006). Studies in Ontario also show an increased use of islands and lake
shorelines during the spring (Bergerud 1985; Cumming and Beange 1987).
Many declines in ungulate populations have been attributed to habitat degradation (Leopold
and Darling 1953; Bradshaw and Hebert 1996). Landscape change and an increase in the
abundance of other ungulate species now limit the ability of caribou to effectively space-away from
predators (Rempel et al. 1997; Wittmer 2004; Latham 2009). Since the early 1900s, moose (Alces
alces) have expanded their distribution throughout B.C. resulting in a numerical and distributional
response of wolves (Bergerud and Elliot 1986; Seip 1992; Spalding 1990). Known as “apparent
competition”, primary prey species such as deer and moose do not compete directly with caribou for
forage or space, but support larger number of wolves that prey on caribou opportunistically (Holt
1977; Bergerud and Elliot 1986; Seip 1992; Wittmer et al. 2005; Latham 2009).
Recent studies in B.C. and Alberta have demonstrated that industrial activities and
associated linear features, including roads, trails, geophysical exploration lines, pipelines, electrical
right-of-ways, cutblocks, and oil and gas wells can negatively affect woodland caribou populations
(Bradshaw et al. 1997, James and Stuart-Smith 2000, Smith et al. 2000, Dyer et al. 2001, Sorensen
et al. 2008). These features can alter the movements, distributions, and population dynamics of
both caribou and wolves. Timber harvesting is one of the primary agents of habitat change. Largescale
harvesting reduces the amount of habitat for caribou and increases the area of early
successional forests favored by moose and other ungulate species (Fuller and Keith 1981, Rempel et
al. 1997, Johnson et al 2004, Nitschke 2008). There is rising concern about how advancing threats
from industry are influencing the ability of sub-populations to survive. Small populations, like the
mountain caribou in the southern portions of B.C., have become isolated from neighboring herds
and are at greater risk of extirpation from random variation and stochastic events (Heard and Vagt,
1998).
Recent evidence suggests that disturbance from recreational activities may also be
contributing to the decline of northern and mountain caribou herds (Seip et al. 2007). Recreational
tenures for commercial purposes have increased in both area and number across the province; these
tenures allow greater access into caribou habitat for snowmobiles and helicopter ski (heli-ski)
operations (McNay and Giguere 2008). As recreational activities expand across alpine areas used
by caribou, herds are forced into less favorable habitats that increase accidental mortalities from
avalanches, increase energy demands used to move across steep terrain and deep snow, as well as
increase the risk of predation (Seip et al. 2007).
4. Management of Woodland Caribou
Across most of B.C., the federal government has listed all three ecotypes of woodland caribou as
“threatened”. Management goals continue to focus on monitoring population levels, restoring and
maintaining appropriate sex and age ratios, and include a required inspection for all human
harvested caribou (populations of northern and boreal ecotypes that are not considered threatened).
In order to continue developing the most effective conservation strategies for species-at-risk,
professionals must rely on the philosophy of their discipline, scientific and traditional ecological
knowledge (TEK) from indigenous communities, as well as educated opinions that come from
expert peers (Stephenson 1982; Mountain Caribou Technical Advisory Committee 2002).
All provinces and territories in Canada must adhere to federal endangered species
legislation. For species listed as “endangered” or “threatened”, SARA (Species at Risk Act 2003)
requires that the responsible jurisdiction, or authority, develop and implement a Recovery Action
Plan. These recovery plans address immediate threats to the species and protects or enhances the
species residence and critical habitat. Two advisory committees were formed in B.C. to provide
Forest Landscapes and Global Change-New Frontiers in Management, Conservation and Restoration. Proceedings of the IUFRO Landscape Ecology
Working Group International Conference, September 21-27, 2010, Bragança, Portugal. J.C. Azevedo, M. Feliciano, J. Castro & M.A. Pinto (eds.) 2010,
Instituto Politécnico de Bragança, Bragança, Portugal.