Otoliths-Lada Canada

Otoliths-Lada Canada Mission: 

Otoliths-Lada Canada (Otolithslada.com) is a private laboratory specializing in fisheries and environmental sciences. We offer services to profit and non-profit organizations such as fisheries companies, governments, and universities. Our services include the assessment of fisheries sustainability and the impact of climate change on communities' livelihoods worldwide. Our expertise lies in analyzing the age and growth information of aquatic animals. Our work is demonstrated in literature that is published in peer reviewed scientific journals.

The unique service that we offer is the age determination of crustaceans using the direct method that we developed in 2012 which we have applied to at least ten species from different locations around the world.

Grant Project Goal(s):

The goal of the project is to assess the potential of using band counts in the stomach gastric mills of the crab species as an age indicator.

Among crustaceans, crab fisheries are considered an important industry in the USA. According to NOAA statistics, in 2022, crab landings reached an amount worth more than US$ 500 million. The blue crab makes up to 50 % of the total amount as it reached US $220 million in 2022. Add to the blue crab, Jonah crab landings made up to US $22 million in 2022. The sustainability of these resources is the main focus of fisheries management scientists and managers. Due to the lack of age information in crustaceans, all stock assessment plans rely entirely on size information to estimate age. The absence of age information in crustaceans triggered this study. Sea Pact funded a preliminary study to investigate the potential of using growth bands in the stomach gastric mill of three crab species (Rock crab, Blue crab and Jonah crab) as age indicator. If confirmed, the stock assessments that inform fisheries management of these species could be substantially improved.

Background:

Fisheries management of fish species primarily relies only on age-based, rather than length-based stock assessment, due to the accuracy of the former method. This type of assessment in crab species requires the availability of age which is determined by counting bands in hard structures such as otoliths. In crustaceans, fisheries management currently relies on only length-based stock assessments due to the absence of a sufficient method for age determination (because of the loss of hard structures during molting).

The novel technique we want to assess for age determination in crab species was developed in 2012 and uses growth bands on the stomach teeth as an age indicator for crab species. Funding for this type of research is often difficult to secure, but holds strong potential to improve crab stock assessments, thus contributing to sustainable management of many crab fisheries.

Key Learnings:

What challenge/need were you facing prior to receiving support from Sea Pact?

As a business owner in Canada, the challenge we had was lack of exposure to the American crab fisheries industry. I was lucky to increase that exposure after receiving the support from Sea Pact.

What changed after being part of Sea Pact’s grant program? What specific outcomes can you share?

After developing the direct method of age determination in crustaceans for the first time in the world in 2012, we have not had the chance to engage with the US crab industry. This changed in 2023 after we acquired the Sea Pact grant. It was the first time for me to be exposed to the industry and we are grateful to Sea Pact.

Assessing the potential of age determination on the blue crab from the U east coast may enhance the understanding of the biology of this important resource in terms of age distribution during different phases of its life cycle. The results of the project may also lead to the beginning of applying age-based stock assessment for the fisheries of this species instead of size-based. If this happens, the maximum sustainable yield could increase for some species.

Are there any key learnings/takeaways that you can share that would benefit the entire industry?

Although the amount of money that is provided by Sea Pact may seem small compared to some other funding opportunities, if a proper proposal is submitted the project will be a first step to a great achievement.

Learn more at Otoliths-Lada Canada

Photo: Stomach teeth (gastric mill ossicles) of a blue crab collected from Virginia, courtesy of Otoliths-Lada Canada.

Photo: Thin section of stomach ossicles of a blue crab showing growth bands (red dots) with green dot representing year 1, courtesy of Otoliths-Lada.