Date: 4/20/26 1:44 pm From: Bill Tweit via Tweeters <tweeters...> Subject: [Tweeters] The Merlin discussion
The Chipping Sparrow/Dark-eyed Junco discussion has been quite informative;
I’d like to offer some thoughts about some aspects of Merlin that have come
up in the conversation.
Everybody seems to agree that Merlin is simply a tool, but then discussions
range well beyond that in terms of expectations and limitations. Merlin’s
inability to accurately discriminate between CHSP and DEJU is a great
opportunity to examine some of our expectations about Merlin, and determine
whether they are realistic. First, why do we expect Merlin to be any
better than a reasonably skilled human observer? It is trained by humans,
so it seems unlikely that it would do better. And reasonably skilled
human observers, a category I consider myself to be in, routinely
experience difficulty separating those two species, for very good reason.
Junco songs are notoriously diverse, the range of trill diversity has
already been discussed well. They also buzz, and on one occasion I
actually encountered a male junco singing a perfect Clay-colored Sparrow
song. Dashed my hopes when I saw it. Bottom line, please do not expect
Merlin to be perfect, even in North America where it is quite good.
Expectations should be even lower in other parts of the globe, but it does
have utility in most areas.
Second, why do we think that use of Merlin has increased the level of error
in the eBird data? There has always been a certain level of error in the
data, and I’ve not seen any evidence that Merlin has either increased or
decreased that level. As a reviewer, I have seen “identified by the field
trip leader” as documentation for many years, which is just as flimsy
documentation as “identified by Merlin”. In both cases, a reviewer will
almost always request the observer to include actual details that will meet
eBird standards for acceptable documentation. And, in most cases, a
reviewer will see it as an opportunity to provide some coaching to
contributors on providing defensible documentation. If the observer
chooses not to provide documentation, then it will not be included in the
public database, which is where error matters. If it is a sighting that
doesn’t require documentation, it will be included in the public database,
which is well-understood to have some low levels of error that requires the
use of statistical tools that are good at detecting signal amidst some
noise, or what we call misidentifications.
Merlin has undoubtedly helped increase the number of new or novice birders,
but is there any evidence that it has changed the ratio of novice:skilled
birders? I’ve not seen such evidence, and my subjective assessment is
that the wave of new birders has been simultaneous with a significant
increase in the number of proficient birders. If the ratio has been
relatively constant over the span of eBird years, then Merlin has not
increased the magnitude of error in the database.
And, let’s not forget that Merlin was built to assist with several
objectives, only one of which is helping birders in the field. It has
another, very significant, purpose: to increase awareness of birds among
the general population. Most of the Merlin users I encounter now are
people who take some joy in finding out what birds are present in their
yard, or on the favorite walking routes, or while they are camping, …
They aren’t contributing sightings to eBird, they just want to know more
about the world around them. It definitely increases environmental
awareness, an entirely separate purpose than helping birders. And an
immensely valuable function. Does it matter to them if Merlin is imperfect
in some ways? Not really. They are just excited and appreciative to put
a name on a mysterious singer, or know that there are at least 15 species
of birds on their morning route. A third purpose is to make birding more
accessible for people with disabilities, and I have had several chances to
speak with people who always enjoyed birds, but found that increasing
physical limitations was making it harder for them to still find pleasure
in it. They demonstrated how they use Merlin to restore some of their
ability to find and experience birds. I don’t know of any statistics on
the proportions of Merlin users who fall into each category, but in my
everyday, non-birding world, I am consistently surprised by the number of
people who are not birders but are fans of Merlin. Without hard data, I
wouldn’t want to make any assumptions about levels of birder vs non-birder
use.
So, let’s be realistic about Merlin. It’s a great tool, but it is just a
tool. Learn it’s limitations in your area, and enjoy it’s strengths.
Kudos to Carol R. for reminding folks that junco/Chippy confusion is one of
those limitations, and offering some tips on how to address it. Don’t
expect Merlin to be super human. And remember, it wasn’t designed just for
eBirders. And, as everyone has said, please, please, please confirm your
detections of unusual birds with more tools than just Merlin.
