Early to mid-May is warbler migration time. For those of us lucky enough to live in the eastern half of the country or in the upper Mid-west, it’s a time we relish and look forward to all winter. All sorts of small colorful warblers are flitting around the tree tops in search of bugs putting a visual sparkle in a warm spring day. In addition, beautiful warbler songs fill the woodlands. But the warbler season is short and fleeting. Just like spring.
There are over 50 warbler species in the US. Each one is small, dainty and often very colorful. Nearly all are woodland residents. They are very active birds, constantly flitting about in search of their next insect snack. Warblers spend about 80 percent of their day searching out insects to eat. I often think, what it would be like if we didn’t have birds to eat all of these insects? No doubt we would be over run with billions of insects. It’s hard to even imagine how bad the bugs would be.
All warblers have short pointed bills, perfect for snatching up insects. Warblers are also acrobats. Their dominative size allows them to hang upside down, cling sideways and just about any other position while seeking out hidden insect meals. They probe flowers, the undersides of leaves and even behind tree bark to find their next bug meal. Some warblers are even known to catch flying insects, snatching them right out of the air in a process called “hawking”.
The preferred habitat for most warbler species is in the tree tops. This is where most of the bugs are found. It makes sense that it’s easier to live where the food is located. Tree top dwelling warblers tend to be brightly colored. There are some ground dwelling warbler species such as the Ovenbird. These warblers also eat a wide variety of bugs but they tend to be drab in color, thus blending into their terrestrial surroundings.
All warblers are very strong flyers. That makes a lot of sense because warblers are true Neo-tropical migrants. This means they spend their winters in the tropics of Central and South America. Each spring they fly thousands of miles to return to their breeding grounds in the upper Midwest. It’s important to note that the warblers are not nesting on their wintering grounds in the tropics. Or at least that is what we have always assumed until recently when it was discovered that a couple species did reproduce in the tropics in the winter after the regular nesting season in the U.S. was over. Not much is known about this very unusual second nesting behavior.
Some warblers nest in cavities such as the Prothonotary Warbler. However the over whelming majority of warblers build a small cup nest in the branches of a tree or on the ground. Warbler nests are small affairs constructed of fine plant material. It is fashioned into a cup shape with the interior part of the cup that fits the female’s body perfectly. They often decorate the outside of the nest to help conceal its location or make it blend into its surroundings.
However what the warblers are best known for is their brightly colored feathers. The Blackburnian Warbler and the Cape May Warblers are good examples. Their striking black and orange colors make them stand out. Other warblers are not colorful but can be very striking. The Black and White Warbler is a good example of this. Their bold black and white markings make them stand out from the other birds.
The songs of warblers are some of the most beautiful songs in the bird world. In general they have high pitched melodic songs. Each phrase is repeated many times and interspersed with secondary songs. A typical warbler song lasts 3-5 seconds and is repeated over and over. A warbler’s song is how the male claims a nesting territory and also serves to attract a female. The combination of the male’s bright colors and beautiful song makes him irresistible to the females.
If you get a chance this spring, be sure to get out and spend some time looking up in the trees. Afterwards you might want to make an appointment with your chiropractor. A stiff neck is one of the drawbacks of spring warbler migration. Until next time
Stan Tekiela is an author / naturalist and wildlife photographer who travels the US to study and photograph wildlife. He can be contacted via his web page at www.naturesmart.com