Relative abundance is the number of birds of a particular species as a percentage of the total bird population of a given area. For the purpose of this guide
abundance is related to detections, versus actual scientific abundance. As birders, we rely on detecting a bird to see and or hear it. While birds might actually be present in higher than detected numbers, detections are how we interact with birds.
Abundant
Found easily in large numbers in appropriate habitat at the right time of year.
Common
Found easily in moderate numbers in appropriate habitat at the right time of year.
Uncommon
Found in small numbers in appropriate habitat at the right time of year.
Rare
Occurs annually in very small numbers. Not to be expected on any given day, but may be found with extended effort over the course of the year.
Occasional
May occur annually as migrant, wintering, or breeding species. Also might have limited range and/or habitat.
Accidental
Highly unpredictable. Not typically found most years, with less than 10-15 historical records.
Irruptive
Represents an irruptive species whose numbers are highly variable from year to year. There may be small to even large numbers present in one year, while in another year it may be absent altogether.
Poorly Known
Distribution, timing, and actual abundance of species not well known. n some cases species may not have accepted records in Utah, but have been reported and likely have some presence.