Wildlife usage indicates increased similarity between reclaimed upland habitat and mature boreal forest in the Athabasca Oil Sands Region of Alberta, Canada

Abstract

While there is no denying that oil sands development in the Athabasca Oil Sands Region (AOSR) has large impacts upon the habitat it disturbs, developers are legally required to return this land to “an equivalent land capability.” While still early in the process of reclamation, land undergoing reclamation offers an opportunity to study factors influencing reclamation success, as well as how reclaimed ecosystems function. As such, an Early Successional Wildlife Dynamics (ESWD) program was created to study how wildlife return to and use reclaimed upland boreal habitat in the AOSR. Wildlife data comprising 182 taxa of mammals, birds, and amphibians, collected between 2011 and 2017 and from five oil sands leases, were compared from multiple habitat types (burned [BRN], cleared [CLR], compensation lakes [COMP], logged [LOG], mature forest [MF], and reclaimed sites [REC]). Overall, similarity of wildlife communities in REC and MF plots varied greatly, even at 33 years since reclamation (31–62% with an average of 52%). However, an average community similarity of 52% so early in the successional process suggests that current reclamation efforts are progressing towards increased similarity compared to mature forest plots. Conversely, our data suggest that REC plots are recovering differently than plots impacted by natural (BRN) or other anthropogenic disturbances (LOG), which is likely due to differences associated with soil reconstruction and development on reclaimed plots. Regardless of the developmental trajectory of reclaimed habitats, progression towards increased wildlife community similarity at REC and MF plots is apparent in our data. While there is no expectation that reclaimed upland habitats will resemble or function identically to naturally occurring boreal forest, the degree of similarity observed in our study suggests that comparable ecological functionality is possible, increasing the probability that oil sands operators will be able to fulfill their regulatory requirements and duty to reclaim regarding wildlife and wildlife habitat.

Opportunistic wetland formation, characterization, and quantification on landforms reclaimed to upland ecosites in the Athabasca Oil Sands Region

“…The spontaneous appearance of wetlands on reclaimed areas presents an opportunity to consider the intentional facilitation of such features (e.g., via surface contouring or targeted plant seeding) as a potential complementary approach to compensating for habitat impacts to the pre-mine boreal landscape. Certainly, the presence of numerous small wetlands (at least 619 at Suncor Base Plant) has the potential to increase the ecological heterogeneity of upland reclaimed landforms, increase wildlife habitat suitability, and provide hydrologic functions (Little-Devito et al 2019;Hawkes and Gerwing 2019). For example, Hawkes and Gerwing (2019) found that wildlife (i.e., small mammal, large mammal, songbird, amphibian) communities on reclaimed uplands across the AOSR exhibited 31-62% (average 52%) similarity within 33 years of reclamation.…”

“…Land reclamation occurs on active oil sands leases (both open pit mines and in-situ operations) concurrent with bitumen extraction activities. Most reclamation in the AOSR has targeted the re-establishment of upland forest habitat that is similar to the surrounding, naturally occurring boreal forest Hawkes and Gerwing 2019), although work aimed at directly reclaiming/restoring wetlands has also occurred. To date, wetland reclamation efforts have resulted in the establishment of numerous shallow open water and marsh wetlands on several surface mining leases including the first two mines established in the region: Syncrude's Mildred Lake lease and Suncor's Base Plant (Daly et al 2009;Daly et al 2010;Daly 2011;Pollard et al 2012;Daly et al 2012;Mollard et al 2015;Ketcheson et al 2016;Vitt et al 2016;Scarlett et al 2017).…”

Immediate response of fish communities and water chemistry to causeway breaching and bridge installation in the Kaouk River estuary, British Columbia, Canada

“…Finally, for the breach and reference sites (B1 and Ref4) that exhibited significant changes in fish communities before and after breaching ( p = 0.01 and 0.002), the contribution of each fish species, including salmonids, to the observed change was explored using a similarities percentages (SIMPER) analysis (Clarke ; Clarke & Ainsworth ; Hawkes & Gerwing ). As part of this analysis we calculated the ratio of each variable's average dissimilarity to the standard deviation of dissimilarities (Diss/SD).…”

Geospatial analysis of the patterns of chemical exposures among biota in the Canadian Oil Sands Region

“…Oil Sands development is changing how wildlife uses the landscape, population densities, and species interactions both during the process of development and reclamation [4,55]. Changes in landscape features (i.e., connectivity) and usage by wildlife can change the predator-prey relationship changing the trophic position where wildlife are feeding [55].…”

“…The Canadian Oil sands, which is comprised of the Athabasca, Cold Lake, and Peace River deposits, covers approximately 142,200 km 2 and is situated in the middle of the Canadian boreal forest [ 3 ]. The Athabasca Oil Sands Region (AOSR) is the most heavily disturbed, where approximately 4,800 km 2 are undergoing surface mineable oil development, of which approximately 895 km 2 have been cleared or disturbed [ 3 , 4 ]. As a result, biota living in this region are exposed to many chemicals, including metals, primarily released during the upgrading of bitumen, and from fugitive dust related to mining activities [ 5 – 7 ].…”