State of Washington Interagency Northern Pike Rapid Response Plan (2023)

The Northern Pike (Esox Lucius) is a non-native fish species classified as an aquatic invasive species (AIS) in the state of Washington that has invaded multiple habitats within the state. Illegal stocking in the 1950s in Montana rivers¹ outside its native range led to establishment of Northern Pike in the upper Columbia River Basin (McMahon and Bennett 1996; Vashro 2018). By the 1970s, they had expanded their range into the Flathead River system and a separate illegal introduction also occurred in the Coeur d’Alene River system (Bernall and Moran 2005). Since that time, Northern Pike have steadily expanded their distribution downstream to include the Pend Oreille River, Spokane River (Bennett and Rich 1990; Scholz et al. 2009), and the Columbia River upstream of Grand Coulee Dam (CTCR et al. 2018). Northern Pike have also been introduced in Lake Washington with the first confirmed capture of a Northern Pike specimen occurring in 2017 and several more Northern Pike captured since (Yuasa 2017).

Northern Pike are highly piscivorous, can live over 20 years, and can grow to over 45 pounds (Wydoski and Whitney 2003). They mature at 2-3 years of age, are highly fecund, and can consume substantial quantities of native salmonids, causing substantial declines in prey populations (Craig 2008; Sepulveda et al. 2014). Northern Pike also have broad physiochemical tolerances allowing them to invade waterbodies with a wide range of water quality conditions (Haugen and Vollestad 2018; Dunker et al. 2022). Given their population dynamics and physiology, it is likely that Northern Pike will eventually expand their distribution into waters throughout the state of Washington. Areas that are at especially high risk of invasion, due to proximity to currently established populations, include portions of the Columbia River downstream of Grand Coulee and Chief Joseph dams and waterbodies connected to Lake Washington. Minimizing negative impacts of Northern Pike where they are currently established and preventing further spread within the state of Washington is critically important for protection of native and important fish species, including Endangered Species Act (ESA)-listed salmonids, as negative impacts to these populations could have dramatic deleterious ecological, cultural, and socioeconomic effects across the Pacific Northwest (Naiman et al. 2012; ISAB 2019). Thus, concerns about the potential impacts of Northern Pike have led the Western Governors’ Association to designate them as a “Top 25” AIS (WGA 2018).

Plan Purpose

The purpose of this Interagency Northern Pike Rapid Response Plan (Plan) is to provide a coordination document and technical resource to enhance the efficiency and effectiveness of Northern Pike prevention efforts, detection, early response, and long-term management activities. These efforts are necessary to minimize environmental, economic, and cultural resource impacts of Northern Pike where they are currently established and prevent further invasion of waterbodies within Washington state to protect native and important fish species.

Plan Goals

1. Minimize the probability of further Northern Pike invasion.
2. Minimize the impact of Northern Pike on native and important fish species.

Plan Objectives

1. Minimize the likelihood of Northern Pike establishment in additional waterbodies of the state of Washington because of human-transport or volitional movement.
2. Increase public awareness of the invasive Northern Pike issue and support for management efforts.
3. Maximize the probability of early detection of Northern Pike in new waters.
4. Establish clear requirements and procedures to enable action within the first 48 hours of a Northern Pike detection.
5. Provide a systematic approach to verify a detection and investigate reported observations of Northern Pike in new waters.
6. Provide clear communication and reporting guidance to trigger extended response activities within 6 weeks of initial detection.
7. Implement scientifically sound management to detect, eradicate, contain, and/or suppress invasive Northern Pike populations.

Plan Overview

The Plan is divided into three general activity classifications: 1) Prevention and Early Detection 2) Rapid Response Activities, and 3) Extended Response Activities. The Plan is organized sequentially to address the following topics:

• Prevention and Early Detection
  • Prevention (Section 3)
  • Routine Monitoring (Section 4.2)
  • Detection Verification (Section 4.3)
• Rapid Response Activities (Section 5)
  • Request and Establish Incident Command System (ICS; Section 5.1)
  • Initial Scoping (Section 5.2)
  • Range Delimitation (Section 5.3)
  • Data Collation (Section 5.4)
  • Multi-Agency Coordination (MAC) Group Meeting (Section 5.5)
• Extended Response Activities (Section 6)
  • Eradication (Section 6.1)
  • Containment (Section 6.2)
  • Long-Term Management (Section 6.3)

Additional technical information is included in the appendices to supplement each topic.

1 https://wdfw.wa.gov/species-habitats/invasive