Seasonal Sightings

Science Behind the Sounds of Summer

An auditory introduction into the habitats at Schlitz Audubon Nature Center will enhance all your summer outdoor experiences. Hiking on a warm and sunny summer day elicits a feast for the senses, as nature is riddled with soundwaves dancing across the air. Silence is a concept long dismissed by flora and fauna. Simple white noise to one person can be an entire life story to another, and the most interesting sound can be easily overlooked when no one understands what it means. Understanding the reasoning behind a sound allows a person to hear it with new ears. It will allow you to go beyond the question of “What is the sound?” to the question of “Why does this sound exist?”

The Gull Who Cried Predator

The only noise that can overshadow the roar of the waves is the cacophonous “YEOW” of gulls. Schlitz Audubon is a stopping point for a variety of gull species. Distinguishing between a Herring Gull and a Ring-billed Gull can be difficult, even for experienced birders. The species cannot be distinguished by vocalizations alone. Two gulls of the same species can have different calls, while two gulls of different species can have indistinguishable calls.

Although research into gull vocalizations is still sparse, they are likely linked to the organized social structures within each colony. The subtle differences in calls can communicate distinctive information. Alarm calls will increase or decrease in frequency depending on the distance and type of threat. Herring gulls will even learn which members of their colony are more skittish, and will start ignoring their alarm calls, as though they are “crying wolf.”  If a more trusted member of the colony sounds alarm, the group will scatter.

Love Ballads of the Amphibians

Moving towards the still water in the ponds may seem like a respite to the boisterousness. But a melodic symphony of noise echoes over the lily pads and duckweed. Cordial ballads of male frogs reverberate while they are looking for a female to share the pond with. Eastern Gray Treefrogs, Green Frogs, and Bullfrogs will call throughout the summer, but American Toads and Spring Peepers will likely finish their concerts by Mid-June. Each sound communicates species, general fitness, body size, territory, and current location to listening females. Male frogs battle to outshine and out-sing others in order to be chosen.

Why the Songbirds Sing

As a birding hotspot, birdsong can be heard while standing at any spot within our 185 acres of land. Singing is energetically expensive for birds. It gives away their locations to potential predators, so singing birds have to balance the risk with the reward. Typically, only male birds have a distinct song. They use it to proclaim and defend territories and to signify the health of the singer in order to attract a mate. These songs tend to be longer, more structured, and melodic to human ears. Calls, a sound that both males and females make, are shorter and used to alert of a nearby threat or inform about an individual’s location or the location of food.

In the orchestra of woodland birds, woodpeckers are the percussion section. Male woodpeckers do not have distinctive songs, but rather use their drumming ability to attract mates. Different species have different patterns of drumming with differing tempos and rhythms. In order to achieve maximum reverberation, woodpeckers will even drum on non-wood objects, such as metal poles or buildings.

The Complexity of Bird Song

The syrinx (the bird’s equivalent of a vocal box) allows the production of two different pitches at once, as well as the ability to move through a range of notes extremely fast. Northern Cardinals can sweep through more notes than are on a piano in less than a second. Most young have to learn how to sing from their parents, and this instills regional dialects, allowing the more successful birds to pass along their successful songs. The developing birds can even listen while still inside the shell, instinctively learning from their parents and surrounding neighbors.

The next time you hike along the trails of the Center, listen closer to the noises around you. Sounds can have more meaning when listened to with greater understanding and knowledge. Closing your eyes and hearing the stories carried throughout the habitats can create a deeper appreciation of the amazing nature found at Schlitz Audubon.