Parasitic mussels induce upstream movement in their fish hosts: early evidence of extended phenotype

Parasites often have a large impact on their hosts and can alter host phenotype to increase their own fitness, a phenomenon known as extended phenotype. Studies demonstrating extended phenotype for non-trophically transmitted parasites are scarce. Unionid mussels have a parasitic life stage adapted to parasitize fish, which can affect host behaviour, habitat use and growth rates, raising the question of whether parasitic freshwater mussels can also manipulate their host fish to compensate for downstream dispersal and to reach habitats favourable for newly excysted juvenile mussels. Wild-caught, parasite-naïve juvenile brown trout (Salmo trutta) were PIT-tagged, half infested with parasitic larvae from the freshwater pearl mussel (Margaritifera margaritifera), and then returned to their home stream. During the following year, trout were tracked to investigate movement and habitat use, and also periodically recaptured to measure growth and condition factor. The infested trout showed signi..., , # Parasitic mussels induce upstream movement in their fish hosts: early evidence of extended phenotype

Dataset DOI: [10.5061/dryad.12jm63z91](10.5061/dryad.12jm63z91)

## Description of the data and file structure

Wild-caught trout were microchipped, half of the individuals were infested with glochidia, then all fish were released back to their home stream. Trout were regularly tracked in the river to measure distance moved and habitat use. Trout were also occasionally recaught to measure growth. 

### Files and variables

Empty cells in dataframes are labeled as \"null\"

#### File: Categorizing_habitat.sav

**Description:**  Provides data on stream mapping
Variables included: 
SID = Section ID
FR = Flow Regime (1= Very slow; 2= Slow; 3= Rapid; 4= Torrential
PS = Primary Substrate (1= mud; 2= sand; 3= pebbels; 4= cobbles; 5= rocks; 6= organic matter)
Width = section width (m)
SS = secondary substrate (1= mud; 2= sand; 3= pebbels; 4= cobbles; 5= rocks; 6= organic matter
height = distanc...,