Spatio-temporal variation in diet among age and sex cohorts of a model generalist bird species, the Great Tit Parus major: new insights revealed by DNA metabarcoding

Dietary variation among cohorts can have a major impact on how populations adapt to environmental variation. Although variation in diet between cohorts and across habitats has been studied in many taxa, this is not true for most birds, especially smaller generalist passerines whose feeding habits are predominantly cryptic. Here we used DNA metabarcoding with next-generation sequencing to assess spatio-temporal dietary variation among age and sex cohorts of the Great Tit Parus major, a model species in avian ecology. Most dietary species were rare but nevertheless collectively made up 30% of the diet, as expected of a generalist. Winter moth Operophtera brumata, a major focus in tit breeding phenology research, was the most prevalent dietary item, but the next ten most prevalent Lepidoterans were collectively four times more important. There was considerable variation in dietary richness and composition among seasons and years. In winter, natural plant and invertebrate species were ..., Dietary data was obtained from Great Tit faecal samples in 2017 and 2018. DNA was extracted from faecal samples, and DNA metabarcoding carried out to identify invertebrate and plant dietary taxa. The data underwent bioinformatic processing to obtain dietary taxa. Lab and bioinformatic work was carried out at Cardiff University in the School of Biosciences. Sampling completeness analysis was conducted. Multivariate generalised linear models and generalised linear mixed models were carried out to examine dietary composition between different age classes, sexes, habitat types, and seasons., , # Spatio-temporal variation in diet among age and sex cohorts of a model generalist bird species, the Great Tit *Parus major*, revealed by DNA metabarcoding

[https://doi.org/10.5061/dryad.7h44j104p](https://doi.org/10.5061/dryad.7h44j104p)

## Description of the data and file structure

Dietary data was obtained from Great Tit faecal samples in 2017 and 2018. 

DNA was extracted from faecal samples, and DNA metabarcoding carried out to identify invertebrate and plant dietary taxa. The data underwent bioinformatic processing to obtain dietary taxa. Lab and bioinformatic work was carried out at Cardiff University in the School of Biosciences.

### Files and variables

#### File: bipartitedata-winter-ageandsex.csv

**Description:** Dataset to create the winter bipartite plots (Figure 6a and 6b).

##### Variables

* taxa: Prey species Latin name
* type: Plant or invertebrate

All other columns from 'adult' to 'decid' are the percentage frequency of occurrence of each prey species for eac...,