DOI: 10.5061/dryad.3tx95x6r6
title: Data from: Patterns of sperm swimming behaviour depend on male mating tactic and spawning environment in chinook salmon

description: Many species exhibit alternative mating tactics (ARTs), with larger,
 socially dominant males competing for females and smaller males adopting
 “sneaker” strategies to exploit fertilisation opportunities without
 competition or courtship. Females typically prefer larger socially
 dominant males, but their ability to manipulate mating or fertilisation
 outcomes is largely unknown. Here, using chinook salmon Oncorhynchus
 tshawytscha, we ask whether the female’s ovarian fluid (OF) differentially
 influences the temporal patterns of sperm swimming in ejaculates from
 non-preferred sneaker (‘parr’) and preferred (dominant) males. We
 demonstrate that OF improves sperm swimming speed and linearity compared
 to river water, regardless of male mating tactic, but also report a novel
 tactic-specific difference in sperm linearity; parr male sperm initially
 maintain straighter trajectories in river water, compared to dominant
 males, but then rapidly change to less linear and more circular paths over
 time. Intriguingly, we show that OF counteracts this change in sperm
 linearity in parr males so that patterns become indistinguishable from
 dominants when parr sperm swim in OF. Together, these results lead us to
 predict that male chinook salmon exhibit differential sperm trait
 investment strategies that depend on reproductive tactic.
description: # Data from: Patterns of sperm swimming behaviour depend on male mating
 tactic and spawning environment in chinook salmon
 [https://doi.org/10.5061/dryad.3tx95x6r6](https://doi.org/10.5061/dryad.3tx95x6r6) ## Description of the data and file structure ### Raw data This file contains all of the raw data analysed for this paper. **Rosengrave_et_data.csv** This file explains all dataset variables accompanying Patterns of sperm swimming behaviour depending on male mating tactics and spawning environment in chinook salmon. **Dataset**: Rosengrave_et_al_data.CSV The file includes the following columns standard to the format: **Column Entry Unit Explanation** A **Sample** Unique ID for each CASA capture B **ID** ID of milt subsample C **Male** Focal male ID D **Tactic** Alternative reproductive tactic of the focal male. H = large 2-year-old male, S = parr (sneaker) male E **Treatment** Medium of sperm activation. RW = river water, OV = ovarian fluid F T**ime seconds **Seconds Time in seconds post sperm activation G **VAP** Micrometres per second "CASA measure - average path velocity, i.e. sperm velocity along a smoothed path." H **VSL** Micrometres per second "CASA measure - straight-line velocity, i.e. velocity in a straght line form the start to end points of the sperm's path." I **VCL** Micrometres per second "CASA measure - curvilinear velocity, i.e. sperm velocity along its swimming path." J **ALH** Micrometres CASA measure - amplitude of lateral head displacement about the sperm's average path. K **BCF** Hertz "CASA measure - beat cross frequency, i.e. average rate that curvilinlear path crosses average path." L **STR** Ratio "CASA measure - straightness, i.e. linearity of sperms average path (VSL/VAP)." M **LIN** Ratio CASA measure - linearity of sperm's curvilinear path (VSL/VCL) N **Motile** Count the number of motile sperm captured via CASA O **Non motile** Count the number of non-motile sperm captured vai CASA P **Total count** Count total of the number of sperm captured via CASA ## Statistical Supplement The R code used for statistical analysis in this study is an R Markdown file. Written by Rowan Lymbery. Source Software R Environment for Statistical Computing. Version: 4.3.1. R Markdwon file **Rosengrave_et_code.R.**