Speaking of Nature: Personal discoveries inspired by Darwin

  • This gorgeous adult yellow-crowned night-heron appeared to be squinting with pleasure as it gave itself a long, luxurious scratch. FOR THE RECORDER/BILL DANIELSON

  • This immature yellow-crowned night-heron is just beginning to show the black feathers that will eventually fill in above and below the eye. FOR THE RECORDER/BILL DANIELSON


Monday, February 12, 2018

Every year, at about this time, the students in my biology classes are introduced to some of the details of the life of Charles Darwin. They learn that he was born in England in 1809. They learn that he was born into a wealthy English family. They learn that he lost his mother when he was only 8 years old and, perhaps as a result of that loss, that he didn’t initially do very well in school.

As my lectures unfold, we discuss the facts of life in 1825, when Charles was sent to Scotland to study medicine. Most “normal” people of that time spent their entire lives within 20 miles of the place of their birth, but Charles, who loved collecting insects, was destined to take one of those epic voyages around the world that capture the imagination. To discuss the details of this great man’s teenage years with my own students, who are living out the days of their early lives, is quite interesting. You can actually see the notion of “possibilities” start to wander across their faces.

One reason that I so particularly enjoy the timing of these lessons is because many of my students will be preparing to go on their own adventures for February break. The reality of “normal” is quite different in 21st Century America. Distances that might have taken Darwin days or weeks to cover aboard the Beagle can now be covered in hours by anybody who can afford an airplane ticket.

Darwin was stunned by the diversity of life that he encountered. He was familiar with the animal life that surrounded his home in Shrewsbury, so his first forays into the new lands that he visited were particularly interesting for him. The exotic plants and animals he encountered made an impression on him everywhere he turned, and the wonderful thing about this sort of personal discovery is that anyone can experience it if they try.

Go to southern Florida, for instance, and you truly visit another world. Here in the Northeast, we have just had another winter storm whereas Florida is expecting temperatures near 80 degrees. Here the lakes and ponds are frozen up tight, whereas the perfume of wet, swampy earth can intoxicate the senses as you wander the walkways of natural areas in sandals and a T-shirt.

Florida is filled with all manner of living things that we might call “exotic,” but the ones that really capture my attention are the birds. In particular, it is the fact that there are so many large birds that can be seen searching for food almost anywhere there is water that’s exciting to me. Ducks and coots, rails and ibises, spoonbills and storks are all relatively easy to see, if you know where to look. My favorites, however, would have to be the herons.

There are several species that can be found in our area, but the only heron that we are likely to accidentally encounter in western Massachusetts is the great blue heron (Ardea herodias). Pick up a modern bird guide, and start flipping through the pages, and you discover that there are something like 13 species that could be described as being heron-ish. Every single species can be found in Florida during the winter, and the first species on the list that is named as a “heron” is perhaps the most exotic member of the group when seen through northern eyes.

The yellow-crowned night-heron (Nyctanassa violacea) is about 24 inches in length and has a rare plumage that features a darker face with a lighter crown. With most birds the crest, if a different color, is usually darker than the face. Up in our area, the only species that come to mind that share the lighter-crown color scheme are bobolinks and golden-crowned kinglets.

The yellow-crowned night-heron will eat just about anything it finds in the shallow waters it patrols for food, but among the herons it is a bit of a specialist that focuses on crustaceans. Known as the “crab-eater” in some parts, this species has a thicker, heavier bill than most other herons, which may be an adaptation to hard-shelled prey.

Another interesting thing about this species is the fact that young yellow-crowned night-herons don’t get their adult plumage until their third year. I have only seen this species twice in my lifetime, but luck was with me and I managed to see both the juvenile and adult plumages on those two occasions. I saw the “first spring” plumage in February of 2013, whereas the adult was seen in April of 2016. In both cases, the birds were just sort of hanging around in cypress trees, but in the case of the adult bird, I was able to walk underneath it because of its favorable position near a boardwalk that day. This beautiful bird was scratching its chin as I stood beneath it trying to capture the amazing color of its eyes.

If you should happen to find yourself heading to warmer climates for the school break, and if you would like to experience a little of the adventure that Darwin felt on his journey in 1831, I would suggest that you find a natural area and go for a walk. Shut off your electronics and lift your head up so your eyes and ears can be filled with the sights and sounds of the remarkable place you have decided to visit. It may be that everything you see is already known to science, but that will not dull the excitement of making your own personal discovery.

Bill Danielson has been a professional writer and nature photographer for 20 years. He has worked for the National Park Service, the US Forest Service and the Massachusetts State Parks and currently teaches high school biology and physics. Visit www.speakingofnature.com for more information, or go to Speaking of Nature on Facebook.