Intro
Background & Rationale
The idea of using the protection of one species to also conserve other species, known as surrogacy (Wiens 2008), has been much debated and examined in scientific literature (Seddon and Leech 2008). The ultimate goal of species surrogacy is to improve management efficiency – reducing management actions, but increasing impact (Simberloff 1998); however, it only has the potential for efficacy in certain situations, with one of the key traits of an effective surrogate species being habitat overlap with the other species also meant to be conserved (Seddon and Leech 2008).
In Alberta, a species with habitat protections such as the grizzly bear (Ursus arctos) (ASRD 2008), becomes a potential surrogacy species candidate. Songbirds, a taxa which contains many species also requiring protection under the Migratory Bird Conventions Act, 1994, is also a group requiring consideration by wildlife managers. Both grizzly bears and songbirds occupy a wide variety of habitats. Grizzly bears use of different types of habitat is variable depending on factors such as sex of the bear or activity, but can include seemingly opposing habitat types such as clear-cuts and interior forest (Nielsen et al 2004; Munro 2006). The songbird taxa contains many "guilds" or sub-sets of species which can specialize on many environmental types, including interior forest or edge (ABMI 2009) and much like grizzly bears, songbird use of habitat types can also vary seasonally (Bowen 2007). In addition to the overlapping broad habitat type that songbirds and grizzly bears may occupy, on a more specific level, grizzly bear uses for sites, such as for insect or fruit foraging (Munro et al 2006) may overlap with songbirds which can also be insectivorous or frugivorous (De Graff et al 1985; Suthers et al 2000).
In Alberta, a species with habitat protections such as the grizzly bear (Ursus arctos) (ASRD 2008), becomes a potential surrogacy species candidate. Songbirds, a taxa which contains many species also requiring protection under the Migratory Bird Conventions Act, 1994, is also a group requiring consideration by wildlife managers. Both grizzly bears and songbirds occupy a wide variety of habitats. Grizzly bears use of different types of habitat is variable depending on factors such as sex of the bear or activity, but can include seemingly opposing habitat types such as clear-cuts and interior forest (Nielsen et al 2004; Munro 2006). The songbird taxa contains many "guilds" or sub-sets of species which can specialize on many environmental types, including interior forest or edge (ABMI 2009) and much like grizzly bears, songbird use of habitat types can also vary seasonally (Bowen 2007). In addition to the overlapping broad habitat type that songbirds and grizzly bears may occupy, on a more specific level, grizzly bear uses for sites, such as for insect or fruit foraging (Munro et al 2006) may overlap with songbirds which can also be insectivorous or frugivorous (De Graff et al 1985; Suthers et al 2000).
Research Objectives
Primary Objective: to determine whether grizzly bear habitat conservation measures have the ability to simultaneously benefit Alberta songbird populations.
In order to draw a conclusion about this potential surrogacy effect, we must address the inter-relationships between more than bird counts at sites of bear and non-bear use; it is also necessary to look at other potentially influencing factors, such as the sex of the bear and the dominant vegetation-type at each site.
The intent of this study is to create information useable by land managers to inform their decision making. As wildlife management is a large component of both industrial and government projects, the surrogacy information provided by this study is intended to indicate areas where multiple species can be conserved through one management action, increasing efficiency; however, given all the potential influencing variables, this study will also provide more specific information to land managers in terms of if only specific types of sites, perhaps used by certain bears, are the most effective.
In order to draw a conclusion about this potential surrogacy effect, we must address the inter-relationships between more than bird counts at sites of bear and non-bear use; it is also necessary to look at other potentially influencing factors, such as the sex of the bear and the dominant vegetation-type at each site.
The intent of this study is to create information useable by land managers to inform their decision making. As wildlife management is a large component of both industrial and government projects, the surrogacy information provided by this study is intended to indicate areas where multiple species can be conserved through one management action, increasing efficiency; however, given all the potential influencing variables, this study will also provide more specific information to land managers in terms of if only specific types of sites, perhaps used by certain bears, are the most effective.
Hypothesis
Because of the high level of variety of habitat types used by grizzly bears as well as the large diversity of songbird species - each individual species also with a set of habitat preferences, it is difficult to predict with a high degree of certainty the strength of the potential surrogacy relationship as a whole (eg. all songbirds lumped into one taxa); broadly stated, I predict that different birds will be associated with different types of sites (sex of the bear), due to varying vegetation at each. I also predict that overall, more species will be associated with grizzly bear use sites (of any type) than non-use sites due to overlapping resource needs (fruigivory and insectivory).
References:
Alberta Biodiversity Monitoring Institute (2009). ABMI Species Pyramid: Guild Definitions and Species Lists. Retrieved from http://ftp.public.abmi.ca/home/publications/documents/205_Holloway_2009-12-22_SpeciesPyramidGuildDefinitionsAndSpeciesLists_ABMI.pdf
Alberta Sustainable Resource Development (2008). Alberta Grizzly Bear Recovery Plan 2008-2013. Retrieved from http://aep.alberta.ca/fish-wildlife/wildlife-management/grizzly-bear-recovery-plan/documents/GrizzlyBear2008-2013-RecoveryPlan-2008.pdf
Bowen, L.T., Moorman, C.E., and Kilgo, J.C. (2007). Seasonal bird use of canopy gaps in a bottomland forest. The Wilson Journal of Ornithology, 119, 77-78.
De Graff, R.M., Tilghman, N.G., and Anderson, S.H. (1995). Foraging guilds of North American birds. Environmental Management, 9, 493-596.
Migratory Birds Convention Act, 1994 (S.C. 1994, c. 22).
Munro, R.H.M., Nielsen, S.E., Price, M.H., Stenhouse, G.B., Boyce, M.S. (2006). Seasonal and diel patterns of grizzly bear diet and activity in west-central Alberta. Journal of Mammology, 87, 1112-1121.
Nielsen, S.E., Boyce, M.S., and Stenhouse, G.B. (2004). Grizzly bears and forestry I. Selection of clearcuts by grizzly bears in west-central Alberta, Canada. Forest Ecology and Management, 199, 51-65.
Seddon, P.J. and Leech, T. (2008). Conservation short cut, or long and winding road? A critique of umbrella species criteria. Oryx, 42, 240-245.
Simberloff, D. (1998). Flagships, Umbrellas and Keystones: Is Single-Species Management Passé in the Landscape Era? Biological Conservation, 83, 247-257.
Suthers, H.B., Bickal, J.M., and Rodewald, P.G. (2000). Use of successional habitat and fruit resources by songbirds during autumn migration in central New Jersey. The Wilson Bulletin, 112, 249-260.
Wiens, J.A., Hayward, G.D., Holthausen, R.S., and Wisdom, M.J.(2008). Using Surrogate Species and Groups for Conservation Planning and Management. BioScience, 58, 241–252.