Critique: Washington Sea Grant Final Report
Geoduck Aquaculture Research Program (GARP)
What is GARP?
The technique of geoduck aquaculture was developed by University of Washington scientists in the 1990s and subsequently given over to industry who implemented commercial application. By 2007, there was significant concern about the potential impact of geoduck aquaculture, which is done by implanting plastic tubes containing hatchery juvenile clams in the beach and later harvesting with hydraulic wands. The legislature mandated investigation, and it commissioned the University of Washington to review the scientific knowledge base and come up with recommendations. Based on UWs review, the legislature stipulated evaluation of “key uncertainties” and there 6 priorities were established. Results were to be published before the end of 2013. The reader is encouraged to carefully read this report, the major elements of which are only 11 pages.
What did they do?
UW Sea Grant authorized studies for only three of the six “required” priorities, which were to look at the questions of 1) the effects of structures used in geoduck aquaculture 2) the effects of commercial harvesting 3) naturally occurring diseases and parasites in the existing geoduck population. They did recruit an additional study already in progress to look at genetic interactions between cultured and wild geoducks addressing a fourth area of required focus. They did not include that actual research in the report, but made significant recommendations based on those studies. The other two questions pertained to the extent of alteration of waters overlying a geoduck site and the impact of sterile triploid geoduck hatchery stock were simply not addressed. It seems that there was not enough money.
What did it cost?
Total cost was $1,550,357. For this, the taxpayers got three peer-reviewed scientific studies and analysis of a fourth.
What did the studies show?
The first study reported is Ecological Effect of the Harvest Phase of Geoduck Clam Aquaculture on Infaunal Communities in Southern Puget Sound, Washington eventually published in the Journal of Shellfish Research in 2015. The 2013 GARP report include a prepublished version. It is important to read the actual published and peer-reviewed scientific paper, as there are many important details which are not evident from reading this GARP summary. The authors conclude that 1) the sites of study were so diverse that it limited the ways they could look at their data. 2) They didn’t see a statistically significant numbers reduction or decrease in biodiversity from geoduck aquaculture harvest 3) they didn’t see a statistically significant spill-over effect on adjacent plots. The problems with this study are lack of strength and that they appear to ignore some of the data. They only looked at 10 of 50 species, essentially ignoring the rest, and ignoring data from GARP’s exhaustive literature search that suggested there should be 165 species on a typical sand/gravel beach. Of those 10 species studied, 3 (30%) were significantly diminished in number, although those species did not “approach local extinction”. They did not identify a “sentinel species”, that is, one that could be followed to assess the overall health of the ecosystem. These limitations are expected in early research, and it is normal to expect that additional work will be needed. You may see a more complete review of this article including a link to the full text version here: https://protecthendersoninlet.org/critique-2/
The next study reported is Effect of Geoduck Aquaculture Gear on Resident and Transient Macrofauna Communities of Puget Sound, Washington published in the Journal of Shellfish Research in 2015. It concludes that geoduck aquaculture significantly effects the abundance, but not the biodiversity of species at the site. This paper has very similar problems to the first one in that it looked at only 12 of 68 species identified. Again, the expected number of 165 species was ignored. The research did not include assessment of the harvest phase. The paper is appropriately self-critical, describing how it is limited because it did not assess cumulative effects, did not include design to assess salmonids, and described effects from “seasonal biofouling by macroalgae” from geoduck hardware. In the abstract of the published paper, it calls itself a “first look” and calls for further studies. Again, these limitations are expected in early research. Please see a more complete critique here with link to the complete published paper:
The study with greatest impact on aquaculture was Resilience of Soft-Sediment Communities after Geoduck Harvest in Samish Bay, Washington authors Horwick and Ruesink of UW. They evaluated the response of native eelgrass to geoduck aquaculture using reference plots to compare before and after effects. The findings were dramatic with 44% reduction of eelgrass after harvest and complete loss 1 year later. Equally important but now completely ignored, is that the authors noted post-harvest decrease in abundance, richness, and diversity of other species which they could not explain solely on the basis of loss of eelgrass biomass. They suspected additional impacts were present beyond those on eelgrass, and suggested further research. Because of these findings, eelgrass surveys are required for all aquaculture permits, but no follow-up on the authors’ suspicion of more extensive effects of geoduck aquaculture has been done that I am aware of.
The study about parasites Characterizing Trends of Native Geoduck Endosymbionts in the Pacific Northwest eventually published in The Journal of Shellfish Research is basic research that may someday prove helpful. They describe newly recognized parasites and say that it’s good to know about them in case there ever is an outbreak, but doesn’t make any predictions or offer recommendations about risks of parasites in cultured geoducks on wild stocks.
How did the GARP report summarize its conclusions?
When I review the two-page section 4 of the GARP report “Research Priorities & Monitoring Recommendations”, it makes me wonder if anyone actually read it.
The very first labeled research priority is “Cumulative effects of geoduck aquaculture”. The highest priority recommendation was for further research to see if keeping a geoduck aquaculture site in one place or adding others nearby had a significant effect. They recommended developing predictive models “1) to evaluate direct and indirect ecosystem effects in scenarios involving future increases in the extent of geoduck aquaculture and 2) identify appropriate indicator species that reflect the broader status of ecosystem health in response to geoduck aquaculture expansion.” Have either of these been done? 10 years later, NO. The report does NOT conclude that geoduck aquaculture is environmentally safe, although specific elements of the report that seem to say so are often cited out of context.
Equally important, Section 4 goes on to devote about half of its space to concerns about the effect that hatchery geoduck plantings may have on wild geoduck stocks. The report never directly states which outside research was used to satisfy the legislative requirements for this investigative priority, but these articles are probably two of the studies that they were looking at:
Maturation, Spawning, and Fecundity of the Farmed Pacific Geoduck Panopea generosa in Puget Sound, Washington, Journal of Shellfish research, Vol 34, 2015
Reduced Genetic Variation and Decreased Effective Number of Breeders in Five Year-Classes of Cultured Geoducks (Panopea generosa), Journal of shellfish research, Vol 34, 2015
The first study found that cultivated geoducks are capable of spawning within 2-3 years of planting and could certainly mix with natives. The second recommended procedures to increase genetic diversity in hatchery stock and suggested that use of triploids should considered to protect wild geoduck populations from genetic impact. Neither study suggests that the wild geoduck population is free from risk of genetic alteration from hatchery stock.
Back to the GARP report, referring to reproductive contribution from geoduck farms, it states “almost nothing is known about settlement of juveniles”. They further go on to say “investigating triploid geoducks is critical for understanding the extent to which triploidy could help prevent genetic change to wild stocks”. For those unfamiliar with the term, triploidy refers to a genetic modification which renders the clam sterile.
The GARP report outlines great concern for genetic impact on wild geoduck from hatchery stock, yet, 10 years later this question is unresolved. We do see rapid expansion of commercial geoduck farming with seemingly little concern for its potential harm.
Summary
Although industry claims that the GARP report supports their methods of geoduck aquaculture, it actually does nothing of the kind. It raises more questions than it answers.
The GARP report gave strong evidence of the detrimental effects on seagrass and raised suspicion that effects on the environment were greater than on just eelgrass. These other possible effects should be investigated.
Although genetic studies about the potential impact of hatchery geoduck on wild stocks were not obtained within the program, the compiling scientists of the GARP report assessed outside scientific studies and recommended caution and further investigation.
The studies about planting and harvest techniques included in the GARP report are described by industry as definitive for establishing geoduck aquaculture as safe for the environment. On detailed review, these studies are significantly limited and do not have the weight necessary to substantiate the marked expansion of geoduck aquaculture that has taken place since 2013. We simply do not know the answers. In particular, the strong recommendations to obtain cumulative, long-term studies have not been met. At best, the studies suggest that the beach is pretty resilient, and may recover from insults if allowed.
A reasonable question to ask is why UW scientists aren’t speaking up about the shortcomings of the GARP report. I don’t know, but I speculate that it’s because the State legislators spent significant taxpayer money and expected to get an answer; UW scientists did what they could in the 6 years given, but it wasn’t enough time to answer all the questions. Politics being what it is, nobody wanted to say that the job would take more time and more money. UW certainly doesn’t want to say they didn’t get the job done (btw, they didn’t get the job done). UW has the prestige of being the “Sea Grant” people, their research programs benefit from that and I’m sure they wouldn’t want their status to be impacted. Moreover, the industry has convinced government that aquaculture is vital to our future (useful, not vital). By repetitively making untrue statements such as that the GARP study shows geoduck aquaculture to be environmentally safe, they seem to have made them into fact.
Finally, it should be noted that one of the major concerns of environmental activists, plastics in the environment, was not a priority at that time and was not even mentioned.
Ron Smith