Habitat protection for sensitive species: Balancing species requirements and human constraints using bioindicators as examples

Abstract

Vertebrates have particular habitat needs as a function of life cycle and reproductive stage. This paper uses four species as examples to illustrate a paradigm of environmental assessment that includes physical, biological, toxicological and human dimensions. Species used include Chinook salmon (Oncorhynchus tshawytscha), northern leopard frog (Rana pipiens), northern pine snake (Pituophis m. melanoleucus), and red knot (Calidris canutus rufa, a sandpiper). The life cycles of these species include reliance on habitats that are aquatic, terrestrial, aerial, or combinations of these. Two species (frog, snake) are sedentary and two (salmon, sandpiper) are long-distance migrants. While some measurement endpoints are similar for all species (reproductive success, longevity, contaminant loads), others vary depending upon life cycle and habitat. Salmon have a restricted breeding habitat requiring coarse sand, moderate current, and high oxygen levels for adequate egg incubation. Leopard frogs require still water of appropriate temperature for development of eggs. Pine snakes require sand compaction sufficient to sustain a nest burrow without collapsing, and full sun penetration to the sand to allow their eggs in underground nests to incubate and hatch. Red knots migrate to high Arctic tundra, but incubate their own eggs, so temperature is less of a constraint, but feedinging habitat is. These habitat differences suggest the measurement endpoints that are essential to assess habitat suitability and to manage habitats to achieve stable and sustainable populations. Habitat use and population stability have implications for human activities for some, but not all species. Salmon are important economically, recreationally, and as part of Native American culture and diet. Red knots are of interest to people mainly because of their long, intercontinental migrations and declining populations. Other measurement endpoints for these four species illustrate the differences and similarities in metrics necessary to assess habitat needs. The implications of these differences are discussed.

Complexity of bioindicator selection for ecological, human, and cultural health: Chinook salmon and red knot as case studies

“…We adopted this approach because we wanted transparency in selecting measurement endpoints and to develop a method that was applicable to other species. The authors have extensive experience with both species in terms of biological aspects, ecological significance, and cultural importance (Burger et al 2008, 2013a, b). …”

“…In this sense, cultural endpoints include a range of other physical, environmental, and economic endpoints. This information is not routinely collected but can be estimated using well-established survey technique (Burger et al 2013a, b)…”

Environmental Assessment for Sustainability and Resiliency for Ecological and Human Health

“…The mature adults enter their original or “natal” river system, migrate upriver, through fish “ladders” past dams, until they reach suitable spawning areas. There they build nests, lay and fertilize eggs, and then die [18,36,52]. End points or metrics can include: 1) number of adult fish passing upriver through a given fish ladder at a dam, per unit time (day, month, season), 2) number of spawning adult salmon/river mile or per time period, 3) number of nests (redds) per river mile, 4) date of first spawning, 5) viability of the fry, 6) weight or condition of spawning adults.…”

“…Sustaining biodiversity is widely recognized as desirable, yet preservation of diverse cultures and communities is an important societal value as well. We have previously proposed that indicators can be selected to provide information about ecological health, human health, and the health of diverse cultures (societal/cultural health) [18,35,36]. For example, preserving fish stocks to maintain healthy populations and to ensure continued fisheries is an important societal goal, but preserving fish populations because they also have an important cultural and societal value independent of fisheries is not always considered in indicator selection, particularly for Tribal Nations [37,38].…”

“…We consider the features that are important for assessment of healthy ecosystems, ecosystem disruptions (natural and anthropogenic), recovery and resiliency, and the effect of ecosystem disruptions on human health. This paper relies on our previous work with monitoring and bio indicators [10,11,18,36,37,46,47] salmon [18,36,48], and stakeholders [33,39,49,50]. It involves a synthesis, amplification, and further development of the types of monitoring that are necessary to address ecological, human, and cultural health and well-being.…”