Main data file #
This dataset contains monitoring data for years 2013-2022. The dataset includes information on broods, adult birds, nestboxes, and acoustic recordings (from 2020 onwards).
File format #
The CSV file has no index column, and the first row contains the column names. The column names provide descriptive labels for each variable in the dataset.
Variable descriptions #
| Column Name | Explanation |
|---|---|
| year | The year when the data was recorded |
| pnum | Nesting attempt identifier, unique to each attempt. It's made up of the year, the number of nesting attempts in the same box that year (1 for the first attempt, 2 for the second attempt in the same box, etc.), and the nest box number. Corresponds to 'ID' in the song dataset (great-tit-hits.csv). |
| nestbox | The name of the nest box. |
| clear_date | The date when the nest box was cleared, indicating the end of a nesting attempt. |
| missing_entire_brood | Indicates whether the entire brood (chicks) is missing or not. |
| suspected_predation | Indicates whether suspected predation occurred during the nesting attempt. |
| lay_date | The date of laying, recorded as the day of the year ("YYYY-MM-DD") when the first egg was seen. |
| april_lay_date | The lay date as an April date, where April 1 is 1. |
| lay_date_visit_interval | The interval in days between the laying date and the nest box visit. |
| laying_rate | The rate of egg-laying, calculated as the number of eggs laid per day. |
| incubation_started | Indicates whether incubation of the eggs has started or not (can disregard) |
| num_broken_eggs | The number of eggs that were broken (accidentally by field workers) during the nesting attempt. |
| hatch_date | The date of hatch, recorded as the day of the year ("YYYY-MM-DD"). |
| april_hatch_date | The hatch date as an April day, with April 1st being 1. |
| incubation_duration | The duration of time that the eggs were incubated, when known when they hatched. |
| total_egg_weight | The total weight of all eggs weighed. We also weigh 3 or 4 eggs to get an average. |
| num_eggs_weighed | The number of eggs weighed. |
| clutch_size | The total number of eggs when incubation starts. |
| num_chicks | The number of chicks that are seen to hatch, counted when first seen hatching and again at around day 5 when faceplate. Some might not be hatched at the first visit, and some might hatch and die and be taken out by parents by the second visit. |
| num_chicks_ringed | The number of chicks that are alive and big enough to take a ring at day 15. |
| april_ring_date | The date when the chicks were ringed ("YYYY-MM-DD"). |
| ring_day | How many days old the chicks were when they were ringed. |
| num_live_chicks | The number of chicks that are alive when they are ringed. |
| num_dead_chicks | The number of chicks that are dead. This can occur on more than one visit. |
| num_fledglings | Calculated by counting the number of chicks left dead in the box after the rest have fledged. |
| mean_chick_weight | The mean weight of chicks at 15 days old. |
| father | The BTO (British Trust for Ornithology) ring of the father, assumed to be the bird feeding the young. |
| mother | The BTO ring of the mother. |
| resident | Indicates whether the bird is a resident or not. |
| natal_box | The nest box where the bird was born. |
| year_born | The year the bird was born, if known. |
| bto_age | The age of the bird (British Trust for Ornithology code) classification. |
| age | The age of the bird. This is exact if the bird was ringed as a pullus in the population, or approximate (based on plumage moult) otherwise. |
| x | The X coordinate (Easting) of the bird's nest box. Uses the British National Grid Eastings and Northings. |
| y | The Y coordinate (Northing) of the bird's nest box. Uses the British National Grid Eastings and Northings. |
| type | The type of nest box (great tit or blue tit -size). |
| poly | The areas of Thiessen polygons formed around all nest boxes, restricting areas to within the perimeter of the woodland (nest box spacing polygons). |
| edge_edi | Edge distance index (EDI). Accounts for the number and distribution of habitat edges in close proximity to the nest box. See: Wilkin, Teddy A., et al. "Edge Effects in the Great Tit: Analyses of Long-Term Data with GIS Techniques." Conservation Biology, vol. 21, no. 5, 2007, pp. 1207–17. JSTOR, http://www.jstor.org/stable/4620944 |
| altitude_m | The nest box altitude in meters. |
| aspect | The aspect of the bird's nest box. Used to calculate northness. |
| northness | The northness value of the bird's nest box. See WILKIN, T.A., PERRINS, C.M. and SHELDON, B.C. (2007), The use of GIS in estimating spatial variation in habitat quality: a case study of lay-date in the Great Tit Parus major. Ibis, 149: 110-118. https://doi.org/10.1111/j.1474-919X.2007.00757.x |
| habitat_type | The type of habitat the nest box is in. |
| soil_type | The type of soil around the nest box. |
| recorded | Indicates whether the bird was recorded or not. |
| total_recordings | The total number of recordings for the bird (1 recording = 1h, quantifies sampling effort) |
| missing_recordings | The number of missing recordings for the bird due to equipment malfunction. |
| first_recorded | The first recorded date for the bird. |
| last_recorded | The last recorded date for the bird. |
| delay | The difference between first recording date and lay_date . |
| n_vocalisations | Number of songs by a bird in the dataset (a good proxy for n songs produced) |
| repertoire_size | The size of the bird's repertoire, i.e., the number of different song types it produced. |