Reconstructing salmon growth trajectories through biochronologies across a highly variable growthscape

Measuring the growth of migratory fish across habitats is difficult because field observations only provide a snapshot into their life; yet, understanding which habitats provide better growth opportunities is crucial for their conservation. We experimentally enclosed individually tagged juvenile Chinook Salmon (Oncorhynchus tshawytscha) in habitats with known differences in growth potentials to evaluate four different models (Dahl-Lea, Fraser-Lee, Biological Intercept, Modified Fry) used to back-calculated size-at-age from otoliths. We found that otolith-derived fish size reconstructions were most accurate using the Biological Intercept or Modified Fry model, though bias remains for slow growing fish. This tool was then used in a case study to reconstruct the mosaic of inter- and intra-habitat growth opportunities available to fishes, providing a useful framework for assessing and monitoring fish responses to habitat restoration and a changing environment., , , # Reconstructing salmon growth trajectories through biochronologies across a highly variable growthscape

[https://doi.org/10.5061/dryad.9zw3r22pt](https://doi.org/10.5061/dryad.9zw3r22pt)

This data repository includes two Excel file datasets, exog_intercept_20210430.csv and increments.csv; three R scripts, 01_data_prep.R, 02_oto_model_comparison.R, and 03_oto_model_application.R; six figures; and three tables. All missing data are represented as NA.

## Description of the data and file structure

### **Data Files**

#### **Exog\_intercept\_20210430.csv**

Description: large dataset of juvenile fish fork length sizes and otolith sizes from various projects, including ones outside of the scope of this project. Excel consists of wide data, where each individual is represented by only one row.

**Variables:**

* lab_id: unique identfier assigned to individual fish.

- project_code: project- specific identifiers, consisting of SBP (Sutter Bypass), DM (Delta monitoring), TT (Tidal Parr), SP...,