SSRAA Chum Overview – July 11, 2019

12
Jul

The 2019 chum season has started, and the early return data and patterns are difficult to interpret but are not generally following the forecast that we did earlier in the year. We didn’t expect many age-5 chum, since the age-4 fish from last year were so weak: the forecast told us that this particular age class was bound to be weak in 2019. The same forecast model also indicated that 2019’s age-4 chum would be strong based on the very strong age-3 returns that we saw in 2018. We also factored in the return strengths from years following runs similar to 2018, which gave us our final forecast for 2019.

So – why are we having a weak start to the chum run that had a promising forecast? The answer is that we don’t know… at least not yet. But we do have some initial information that points in directions that we will eventually be able to make conclusions on. A list of what we know right now looks like this:

  • All sites in SE Alaska are experiencing the same issue: early returns that are much weaker than forecast and are trending late.
  • The weather has been persistently dry and warm. Even among the recent warm and dry summers, 2019 is shaping up to set records. From what we have seen and experienced in the past, this type of weather phenomena is very negative in terms of chum behavior: the fish will hold deep and/or not move into fishing districts and/or terminal areas. The fish that do make it back to terminal areas will not readily recruit into the raceways for us to take as
  • The run is late. We were not surprised by the slow start of the season due to the weak age-5 prediction, which tends to be the first age class caught in the fishery. However, even the age-4 chum appear to be at least a week late, and could easily be substantially more than that. Every day that the run curve is later, the less time we have to collect broodstock, prosecute cost recovery, and provide opportunity. We’ve had years recently, 2016 and 2017 specifically, when the run was a couple weeks early, which is also anomalous but doesn’t quite create the cascading series of problems that a late run does.
  • The sex ratios appear to be tracking. Although we look at these ratios most closely in the cost recovery fishery so that we can properly manage the terminal areas for brood and cost recovery, we also have data from the processors which indicate a somewhat late run, especially when you factor in the very high male percentage from the sibling age-3 fish last year: all things being equal we would expect more age-4 females this year.
  • There is a high percentage of unmarked fish this year. This is typically an indicator that we are early in the run, with unmarked fish comprising 15-20% of the catch in 101 and 102 for the first couple of weeks of the season. However, this unmarked contribution usually drops to less than 5% of the catch after the first couple weeks of fishing. Because there is nothing to indicate that our hatchery fish would be surviving at any different rate than their unmarked counterparts, we are hopeful that this is further evidence that the run is late.
  • The Neets Bay and Burnett Inlet SHAs have seen very few chum thus far. This is alarming and we’re becoming very anxious to see chum schooling in these areas which are so critical for our operations. In normal years we would be working away on cost recovery on July 11 and be ready to put fish over the barrier and be taking eggs at Neets in about a week from now. We would also be seeing schooling fish pushing to the head of the Bay. This year, it is quiet at the head of the Bay, and the small troll fleet from Bug Island to Chin Point are catching barely enough to make it worthwhile.
  • The otoliths we’re reading in the distant fisheries (Districts 1,2,4 and 6) are showing that Neets and Burnett fish percentages are trending lower than normal. This is also quite alarming, and we need to have these percentages rise in order for these sites to be successful in their multiple goals (brood, cost recovery and opportunity).

In terms of what SSRAA’s game plan is, with what we see at this point in time: we’ll wait and watch after this weekend’s catch. We assume that there will be a seine opener on Sunday and we’ll get some otolith reads from it by Tuesday. Then we will have to make a decision on whether preservation of broodstock is enough of a concern to warrant closing down chum trolling from Bug Island to Chin Point, which at this point is one of the only management tools that we have. The days are getting short for this to turn around, and it will be more and more difficult to accomplish all the goals that this organization has. But we hope to release new information next week that will be more encouraging – stay tuned.

Current chum catch by site: