Deterring Seal Predation at the Locks
Spawning salmon returning from the ocean to the Greater Lake Washington Watershed and our own Issaquah Creek are getting a helping hand to get past predators at the Ballard Locks. That is where many Issaquah chinook and coho – squeezed into a small space to navigate the fish ladder into fresh water – are getting waylaid and devoured by hungry harbor seals.
And it is not just the adult salmon that become dinner for seals. Smolts migrating from the Issaquah Salmon Hatchery out to the ocean spend several months just below the locks as they adapt to saltwater, and many become snacks for the resident harbor seals. The U.S. Army Corps of Engineers, in partnership with non-profits and tribes, is experimenting with a new noise-making technology that will deter salmon-fishing by seals and potentially improve the salmon survival rates.
According to the Seattle Times:
A new gadget is being tested at the locks, intended to startle seals to deter them. The so-called Targeted Acoustic Startle Technology, developed by scientists from the Sea Mammal Research Unit at the University of St. Andrews, is marketed by GenusWave Ltd. based in Edinburgh, Scotland. The device was made for use at fish farms, to keep seals away from net pens. The device is housed in a metal canister that looks like an upscale water bottle, and produces a sound played through two underwater speakers at randomized intervals. The sound it makes is not particularly loud or unpleasant … to a person. The acoustic technology replaces conventional, loud noisemakers that seals just get used to. The sound made by the startle device provokes a flight response — a fundamental mammalian reflex — without causing harm to the seal, or bothering salmon.”
UPDATE: Get your Hatchery Tour Tickets!
We are excited to announce that we are now conducting small group hatchery tours! To ensure everyone’s protection, here are the special guidelines:
- Tours are limited to 5 people or less, pursuant to State of WA/ King County guidelines for Phase 2.
- All visitors will be required to have their temperatures taken, and wear masks. (If they don’t have a mask, one will be provided.)
- Email addresses will be required at check in.
- All visitors must be escorted by a FISH docent.
- All of the tour will occur outdoors on the hatchery grounds.
- Social distancing will observed as outlined in Phase 2 guidance.
- Tickets will be available on eventbrite.
- Tickets are free, with donations encouraged.
- Tours times will be listed on eventbrite (according to docents’ availability).
Entry to the hatchery grounds is restricted exclusively to ticket holders during their allotted tour time. The hatchery is currently closed to walk-up visitors.
We look forward to sharing the wonders of salmon with you this season.
Big Chinook Return! Small Spawning Results. Why is That?
Wednesday, Sept. 23, 2020: The forecasted chinook return to the Issaquah Salmon Hatchery was about 4,000 fish. The number counted through the Chittenden Locks was 12,780 as of 09/20. What?!? Historically, 50 to 70% of the fish counted through the Locks make it to the Issaquah hatchery. Some of the chinook are headed to the Cedar River, where they are considered an endangered population, but most are headed our way.
Another brush with reality: this time, the males outnumbered the females almost 3 to 1! We know that pinnipeds (and our beloved orcas) prefer female chinook – they are loaded with fat and protein-filled eggs, but this season that tendency is extreme.
The WDFW set a pretty high bar to assure the safety of the staff and volunteers at the spawning shed, but the shortfall of female chinook made it a short day, resulting in 328,000 fertilized eggs — a small but significant step to the 3,200,000 chinook egg goal for the year. The holding pond is full, the creek is full, so we are on a good path to meeting the goal.
What can we conclude from this?
Salmon return forecasting is even tougher than weather forecasting. And, we need to get good data on where the female attrition is happening, and whether something can be done about that.
Please note that the WDFW is not allowing tours on Tuesdays, spawning days, as keeping staff, volunteers and possible visitors safe is paramount.
A Second Transfer of Kokanee to Orcas Island!
Hatchery Spring Release Report
Greetings, FISH friends! Today we present our spring fish release numbers — plus important information on a chinook study being launched by the Washington Department of Fish and Wildlife to try to better understand and combat fish predation on our outgoing salmon smolt. It’s a really important issue, and let’s hope this study brings the results we need. Read on…
- 6,500 planted in Beaver Lake
- 8,500 planted in Lake Desire
- 3,100,000 released in Issaquah Creek
- 465,000 released in Issaquah Creek
PIT TAG STUDY:
The Washington Department of Fish and Wildlife is running a study this spring, putting PIT tags into chinook smolt and releasing them over a range of time. The study will test the theory that if they are released early, when the lake water is cold, those warm-water fish that account for a great deal of the predation our smolt face have not fully woken up, and more of the smolts will make it across the lake. The PIT tags will be detected in several locations, including their passage through Chittenden Locks to Puget Sound, allowing the WDFW to better understand the predation issues with these young fish and to put into place better practices for the survival of our own salmon. A total of 5,000 tagged fish are planned to be released over the course of the spring releases. The study was made possible through a generous grant from the Candy & Don Havens Foundation
- Chinook Spawning Season Final Report 2020
- Spawning Update – Oct. 9, 2020
- Chinook Gives Its All (Including its Tail?)
- Updated: Mystery Tags on this Year’s Return
- Small Group Tours are Going Swimmingly!
- Deterring Seal Predation at the Locks
- UPDATE: Get your Hatchery Tour Tickets!
- Big Chinook Return! Small Spawning Results. Why is That?
- A Second Transfer of Kokanee to Orcas Island!
- Hatchery Spring Release Report