We are pleased to announce the arrival of the Acceptable Breeding Codes Chart! This document was on the wish list for many atlasers and project staff and we finally had the time to construct what will be a valuable reference. Bookmark this chart because it may become one of your best friends during the breeding season!
Acceptable Breeding Codes Chart (pdf version)
Acceptable Breeding Codes Chart (editable xlsx version)
What is it?
The Acceptable Breeding Codes Chart is a reference where you can look up the suitability of any breeding code for every breeding species in Wisconsin. There is a number on the chart (1 to 4) where each code (column) meets each species (row). This is an index that takes into account the life history of the bird using information from Cornell’s Birds of North America (reminder, atlasers get a discount subscription with code: WBBA2) as well as the status of that species in Wisconsin. The resulting number defines the suitability of each breeding code for each species in the state, from “use freely” to “do not use”.
1 = Likely to be witnessed in appropriate habitat and season. Use code freely.
2 = Reasonable in appropriate habitat and season if care is taken when assigning code.
3 = Only occasionally witnessed in appropriate habitat and season. Please provide comments.
4 = Very unlikely or impossible, even in appropriate habitat and season. Provide detailed comments.
How do you use it?
Use this chart if you’re questioning which breeding code is appropriate for your observation. The lower the number on the chart, the more likely that species exhibits the code in question. Keep in mind that the chart assumes that the date and habitat support use of the code. If one or both of these are marginal, the likelihood that the code is legitimate decreases. Breeding date information can be found on the Breeding Guideline Bar Chart.
The atlas breeding codes
If you need a refresher, the breeding codes are here:
For definitions, explanations, and examples, see the Breeding Criteria and Codes document.
How will it be used at Atlas Central?
First of all, many of us at the atlas staff will use this as a reference when we have questions. Yes, even the “experts” run into difficult judgement calls!
We will also be using this chart to filter and review atlas records on the back end. This will help data quality, but note there will be no front end filtering, so ideally you are using this chart to do the best you can when you submit data. One of the biggest improvements over the first atlas is our ability to review records for WBBA II. We will review records in several ways, the most significant of which will be running all atlas records through this document as a script. The codes with 1 and 2 will be allowed and those with 3 or 4 will be flagged and evaluated. So, you may be asked for more details about records which have a 3 or 4 for the given code, especially if you did not provide adequate comments.
This should be a user-friendly reference, not something to overwhelm you!
It may be easy to get lost in this long chart and intimidated by its detail. There is no reason to try to memorize this chart or to cross-reference every past sighting of yours with it. The purpose of this chart is just to reference when you aren’t sure how to code a situation or if you don’t know if a code is acceptable for a certain species. So use it however it helps you most!
Ruby-throated Hummingbird – not to be used with S, S7, M, B, or DD. But you knew that already.
Highlights of the Chart
One of the useful parts of this chart is that a quick skim will reveal which codes are usable and unusable for families. It also points out outliers, or species with different behavior or life history that makes their coding rules different than other closely-related species. Here are some of the most important trends that this chart points out:
- Several species cannot be coded as S or S7 because they do not have a song or other noise used exclusively in the breeding season to communicate they are on territory. This includes but is not limited to all geese and ducks, almost all waders, all accipiters and some other birds of prey, all gulls and terns, Ruby-throated Hummingbird, Belted Kingfisher, all corvids, and Cedar Waxwing.
- We’re used to using the B code for woodpeckers and wrens but it also applies to coots, gallinules, and some shorebirds, gulls, and terns, which are known to also build dummy nests!
- While quite a few species can possibly use a Distraction Display (DD), it is only common enough in a few such Killdeer, Ruffed Grouse, and Mourning Dove, to use without including comments. Since this code is an automatic breeding confirmation, we are particularly careful when reviewing these records. See our prior story on this.
- Some landbirds such as doves, nightjars, Northern Flicker, Pileated Woodpecker, and most finches exclusively regurgitate food to young so the CF code should not be used.
- The UN code, used if you discover an old nest that is not currently being used, should be used with caution for all but a few species with very distinctive nests.
The Tricky Coding Series articles are archived and many involve detailed explanations of these situations, so please look there for more explanation.
Please provide feedback!
Just like the Breeding Guideline Bar Chart, this is a work in progress and likely is not perfect. If you believe you found a mistake or are wondering why something is marked the way it is, as always, there are many ways to contact us. Email us at atlas@wsobirds.org, ask us in the Atlas Forum, or ask a question/ start a conversation in the Facebook Breeding Bird Atlas Birds and Discussion group.
Special thanks to Tom Prestby for doing most of the legwork to prepare the chart, and to Nick Walton for generating the R code we’ll use with this chart to screen records.