Katie Barnas

Native invaders – challenges for science, management, policy, and society

The term “invader” is typically paired with adjectives such as “non-native” and “alien”, yet native species can also cause ecological and economic impacts that rival those of well-known invasive species. By spreading within their historical range, attaining extreme abundances, and exerting severe per-capita effects as a result of predation or competition, native invaders can create an unusual set of challenges for science, management, policy, and society. Identifying when, where, and why species become invaders in their native ranges requires additional scientific inquiry, outside the current focus of invasion biology. Management strategies often mitigate the symptoms rather than address the causes of problematic native species invasions. Convincing stakeholders to comply with management actions aimed at controlling native invaders creates societal challenges and policy makers must prioritize goals from varied and often conflicting human interests. We illustrate these challenges by highlighting native spe...

Nonindigenous Species of the Pacific Northwest: An Overlooked Risk to Endangered Salmon?

Nonindigenous species, which are associated with the decline of many threatened and endangered species, are a major threat to global diversity. This risk extends to salmonids, the most widespread threatened and endangered species in the Pacific Northwest. Pacific salmonids traverse large geographic areas that include freshwater, estuarine, and ocean habitats in which they encounter numerous nonnative species. For this article, we examined the extent to which introduced species are a risk to threatened and endangered salmon. We identified all documented nonindigenous species in the Pacific Northwest, including fish, invertebrates, birds, plants, and amphibians. Where data exist, we quantified the impact of nonindigenous species on threatened and endangered salmonids. The results indicate that the effect of nonindigenous species on salmon could equal or exceed that of four commonly addressed causes of adverse impacts—habitat alteration, harvest, hatcheries, and the hydrosystem; we suggest that managing nonindigenous species may be imperative for salmon recovery.

Smallmouth Bass in the Pacific Northwest: A Threat to Native Species; a Benefit for Anglers

As a popular sportfish, smallmouth bass (Micropterus dolomieu) generates considerable angling opportunities with benefits to local economies even outside of their native range. Smallmouth bass was first introduced to the Pacific Northwest region of North America as a sportfish over 80 years ago, and this species is now widely distributed. More recently, smallmouth bass have become a large component of the fish community in many streams, rivers, and lakes. Smallmouth bass thrive in the Pacific Northwest largely due to the habitat created by human modifications of the landscape. While a desired sportfish, smallmouth bass may also negatively affect native fishes. Of greatest concern is predation on threatened and endangered Pacific salmon; however, the current level of knowledge is inadequate to make informed management decisions for smallmouth bass. Management options for smallmouth bass are complicated further because fisheries agencies are simultaneously charged with enhancing fishing opportunities and controlling predators of threatened and endangered salmon. To advance conservation science, there is a need to determine the utility of different management approaches, and testing options in key areas of overlap between smallmouth bass and salmon is suggested.

Is habitat restoration targeting relevant ecological needs for endangered species? Using Pacific Salmon as a case study

Conservation and recovery plans for endangered species around the world, including the US Endangered Species Act (ESA), rely on habitat assessments for data, conclusions and planning of short and long-term management strategies. In the Pacific Northwest of the United States, hundreds of millions of dollars (

The Challenges of Tracking Habitat Restoration at Various Spatial Scales

US) per year are spent on thousands of restoration projects across the extent of ESA-listed Pacific salmon—often without clearly connecting restoration actions to ecosystem and population needs. Numerous decentralized administrative units select and fund projects based on agency/organization needs or availability of funds with little or no centralized planning nor post-project monitoring. The need therefore arises for metrics to identify whether ecosystem and species level restoration needs are being met by the assemblage of implemented projects. We reviewed habitat assessments and recovery plans to identify ecological needs and statistically compared these to the distribution of co-located restoratio...

Synthesizing U.S. River Restoration Efforts

Evaluating the ecological effectiveness of the hundreds of millions of dollars invested to recover Pacific Northwest salmon has a number of prerequisites— principally, detailed knowledge of management actions. In the absence of coordinated ecological monitoring, basic restoration project metadata (type, location, timing, etc.) is the primary source of information guiding restoration planning and management decisions. There are surprisingly few sources of habitat restoration information at scales appropriate to salmon recovery, ranging from small sub-watersheds to multistate evolutionarily significant units. We evaluate the consistency of two Columbia River basin restoration inventories developed in different ways but similar in goal: to inform future project placement. We compared the Pacific Northwest Habitat Project Database, compiled by researchers at NOAA Fisheries Service, and the Subbasin Inventories, compiled by local entities within each of 62 subbasins. Confederating these two data holdings, we f...