Doe Kag Wats: A Revered Site

Project Overview

The kelp forest at Doe Kag Wats/Jeff Head was lost in the late 1980s/early 1990s, as were most of the kelp forests around nearby Bainbridge Island. Within the Central Sound home waters of the Suquamish Tribe, there has been an estimated 80% loss of floating kelp beds, and a consequent loss of all the services that kelp forests provided.

In 2010, following other collaborative efforts to restore native species in Puget Sound, the Chairman of the Suquamish Tribe asked Puget Sound Restoration Fund (PSRF) to try to restore the bull kelp forest near Doe Kag Wats/Jeff Head. Kelp forest restoration at the time was non-existent in Puget Sound, and in its infancy globally. Methods would therefore need to be developed from scratch to suit conditions at this site.

Implementation

PSRF’s kelp collaboration with the Suquamish Tribe has aimed at developing a restoration practice that can successfully re-grow a self-sustaining bull kelp forest at Doe Kag Wats. Early experiments tested methods, timing, and outplant materials.  Follow-on efforts have built broad support for kelp restoration to help sustain the effort. For the last five years, beginning in 2020, PSRF grew a kelp forest every year (2020–2024) from seafloor to sea surface at Doe Kag Wats/Jeff Head.

PSRF’s approach to bull kelp restoration is ‘to grow a forest to restore a forest’, using modified aquaculture techniques. A seeded kelp forest that successfully grows through the season introduces reproductive material to the site that can potentially catalyze natural kelp recruitment the following year. Further, canopy kelp that grows throughout the water column creates structured conditions in which kelp propagules may more effectively settle at the site. This kind of “adult facilitation” provided by a mature kelp bed is missing in locations where kelp forests have been lost entirely.

Specific techniques used at the Doe Kag Wats site from 2020–2024, encompass propagation and outplanting. Kelp seed on twine is propagated in PSRF’s Kelp Lab, from either wild sporulation or germplasm archived in PSRF’s seed bank.  Approximately 1,500 ft (450 m) of seeded line is outplanted at the enhancement site by PSRF’s scientific divers in winter, wrapped around a cultivation line that is anchored in place and suspended 1 to 2 ft (0.5 m) above the substrate. Anchor blocks are also occasionally wrapped with seeded line. Both the timing and the technique give the bull kelp a chance to grow above the substrate, before understory kelps have a chance to cover the substrate and bury the seeded line. Staggered timing of seasonal outplanting is part of the ongoing plan.

In 2024, PSRF divers documented naturally growing bull kelp at Doe Kag Wats within the kelp enhancement area.  Divers counted 33 bull kelps naturally settled within the enhancement area in May 2024, near or alongside the cultivation lines.  While this level of natural recruitment does not yet generate a self-sustaining site, it is a step in the right direction. The Tribe understands enhancements are not a quick win, or a guaranteed win. Regardless, they want to support ongoing kelp restoration actions.

Alongside bull kelp restoration efforts, the Tribe is also working to address stressors that have potentially contributed to kelp forest losses. These are dual, interconnected strategies.  Specifically, the Tribe is working to address pollution threats from multiple sources that impair seawater conditions.

Key Findings

• Building a successful restoration project starts with co-developing goals to meet the needs of the community you are serving.
• Restoration actions must be tailored to specific sites and place-based knowledge is critical.
• Repeated, successful growth of a kelp bed at Doe Kag Wats is evidence that environmental conditions at this site can still support bull kelp. A continued input of kelp seed is needed at this site, suggesting that conditions that lead to a lack of microscopic forms or to interruptions to reproduction and development might be contributing to kelp decline.
• Stressful temperatures at Doe Kag Wats have been recorded which may be a cause of variability in kelp success. This suggests the need for restoration strategies that are resilient to climate change.
• In adapting aquaculture methods for use in restoration, careful lab practice, site-specific timing within the year, density of seed outplant, and outplant substrate are key components to consider.
• Scaling up is logistically challenging, therefore evidence of return on investment (bigger outplant yielding more next-generation kelps) is an important validation of efforts.
• Differences in seasonality of growth, reproduction, and natural death between the outplant site and wild sites might provide clues to improving restoration technique.

There are many related questions still to explore. Those that we are already working on include trial outplants at Washington sites with different characteristics, approaches to augmenting declining kelp beds, and assessing ecological functions provided by this type of restoration.