The Common Loon (Gavia immer) achieves iconic status in my part of the country.  Its distinct wail prompts images of unspoiled wilderness.  A sighting on a lake evokes thoughts of solitude and grace.  The loon conveys such a definitive image that it is often used as a symbol for nature itself.  

However, we also know this is a special bird in an increasingly threatening environment.

Common Loon
Photo 96749559 / Common Loon © Brian Lasenby |

So, perhaps you will be surprised to learn that the Common Loon is not a federally protected species.  I assumed it was!  However, the birds are classified globally as a species of least concern.  If you are cringing as you read that, you are not alone. 

Loons are subject to several threats to their survival.   Sometimes, loons feeding on minnows mistakenly ingest lead fishing sinkers resulting in lead poisoning.  Boats also create another set of threats. Direct strikes are not uncommon nor are the boats’ wakes that can flood onshore nests.  In some locations, mercury in the water accumulates as a toxin in the fish that the birds eat.  Life is not easy for this symbol of nature.  

Consequently, there are many local conservation groups dedicated to raising awareness and it may be helping, at least a little.  

Consider the annual loon count results:  

  • In Maine, volunteers have been doing a snapshot count across the same slice of the state for 38 years.  While the 2021 count didn’t reveal a larger population than recent years, the loons have doubled their numbers since the dangerous low count of 1983.  
  • In Vermont, the loon population has steadily rebounded from a low of 8 nesting pairs in 1983 (yikes!) to 101 nesting pairs in 2019.  
  • In Minnesota, the loon population remains stable with an average of 2 loons per 100 acres of lake within the six survey areas. 
  • Sadly, another study in Ontario, shows the numbers continuing to decline.  

Loons are quite territorial.  According to a study published in the 1950s, a loon pair will occupy a territory of 15-100 acres, depending on the nesting site availability.  This territorial need creates a unique and perhaps bizarre behavior. 

Recently, a biologist in Minnesota reported observing that territorial loons (ones reproducing) intrude more often into neighboring territories where the nesting pair has chicks than do younger, non-territorial (non-reproductive) floaters that are looking to find and settle on an unclaimed territory.  One might think that the floaters would be looking to disrupt the reproducing loons, not another loon family.   

 A study published in Behavioral Ecology in 2006 also described this behavior.  After considering a couple of other reasons that might prompt this behavior, the research team believes that the intrusive loons are prospecting for habitat that they believe indicate reproductive success, proven by the presence of chicks.  One nesting pair will attempt to displace another to secure the best chase of success for their offspring!

Our uncommon, iconic loon appears to be among other things, a fiercely competitive parent.  


More about loons in Maine –

More about loons in Vermont –

More about loons in Minnesota –

More about loons in Ontario, Canada –

More about territorial incursions by loons –

2 thoughts on “Common Loon, An Uncommon Bird

  1. Любовь says:

    Loons swim like you paddle a canoe: twisting the blade (the foot) on the return stroke to minimize drag. The skull of a common loon is thick and heavy for a bird, and some of its bones are solid, uncommon in birds. This adds weight, which makes it easier for the bird to dive.

Leave a Reply

Your email address will not be published. Required fields are marked *

You may use these HTML tags and attributes:

<a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <s> <strike> <strong>