Growth and longevity of the endangered freshwater pearl mussel (Margaritifera margaritifera): Implications for conservation and management

Key life-history data, such as growth and age, are necessary to effectively manage and conserve threatened freshwater mussel species. Traditionally growth and age studies require large yet destructive sample sizes covering all age classes. Such methods pose a risk to populations of conservation concern, and therefore alternative methods that need only limited sample sizes are necessitated to prevent further threats to such populations. We applied retrospective shell growth at age reconstructions to 98 critically endangered freshwater pearl mussel (FPM) individuals from 34 populations across Finland and Sweden, enabling the use of extremely small sample sizes (n = 1–6 per population). We compared the performance of six different growth models with the reconstructed size-at-age data across FPM juvenile (<20 years old) and adult life stages. The growth reconstruction model showed reasonable skill in reconstructing FPM growth patterns. The von Bertalanffy model was shown to be a good gen..., , , # Data from: Growth and longevity of the endangered freshwater pearl mussel (*Margaritifera margaritifera*): Implications for conservation and management

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Authors and correspondence:
Sabrina Nykänen, [[e-mail]](mailto:[e-mail]), [https://orcid.org/0000-0001-6808-8457](https://orcid.org/0000-0001-6808-8457)
Jouni Taskinen, [[e-mail]](mailto:[e-mail]), [https://orcid.org/0000-0003-0098-9560](https://orcid.org/0000-0003-0098-9560)
Mahsa Hajisafarali, [[e-mail]](mailto:[e-mail])
Anna Kuparinen, [[e-mail]](mailto:[e-mail]), [https://orcid.org/0000-0002-7807-8946](https://orcid.org/0000-0002-7807-8946)

### Description of the data and file structure

**This section consists of the following files:**

\"**A_cor.xlsx**\" - Table containing the age of the corroded shell area (i.e. the number of missing increments)

\"ID\" = identifier of the mussel individuals
\"A_cor...