Sex of the Wildlife Kind

06/06/2014 05:52 pm ET | Updated Aug 06, 2014
  • Mark Hostetler Professor, Department of Wildlife Ecology & Conservation, University of Florida


American Alligator. Photo Credit Milt Putnam

We have entered that time of year when wildlife activity has increased quite dramatically. If you live near water, you may have heard the cornucopia of frogs calling; songbirds are waking you up in the morning with their melodies; woodpeckers drumming on trees, insects are making a racket day and night; and even alligators growling and displaying. Most people may know what is going on -- animals trying to "meet" each other, but the range of activities is quite amazing. Below, I try to interpret the various animal antics during the spring and the summer.

1. Frogs and toads: By far, the most common question I get is, "Why are these frogs/toads so loud?" "Can I do anything to get them to be quiet?" As some of you guessed, it is all about sex. The noise you hear are male frogs and toads calling as loud and often as possible and the message is -- come hither, mate with me! See this bullfrog calling; this western chorus frog; lots of frogs calling, and this American toad. By the way -- bullfrogs eat anything! Now, these calls can be quite vociferous and many, especially after a good rain event that was preceded by a drought. The depressions around a neighborhood fill up with water and these temporary pools are prime breeding habitat. Why? Well they are devoid of fish and without these predators, the tadpoles have a fighting chance.

The males are positioning themselves in and around these pools to attract females to fertilize the eggs that they lay in the water. By the way, if you see the gelatinous eggs that are in a ball, these are frog eggs. If they are in strings, they are toads (see photos here). The calls you hear are usually a mixture of different species, and you can determine the species by matching the calls (see here). Frogs and toads spend quite a bit of energy on vocalization. For example, with spring peepers, males have vocalization muscles that make up 15 percent of their body mass whereas only 3 percent in females. A lot of effort goes into calling -- sit back and enjoy nature's orchestra -- or buy a good pair of earplugs.

2. Woodpeckers: What is that drumming? And why on my house? The drumming that woodpeckers do is also species-specific and the drumming is marking territories and attracting mates. Now, the male woodpecker may have found a spot on your house that has good sound. They come back day-after-day to this spot to amplify their sound (see woodpecker drumming on metal). The sound may be annoying, but do check where they are drumming. The worst case scenario is that they are actually foraging and looking for insects in your decaying siding. You can stop the drumming by placing up a bit of flashing or netting to change the sound and prevent access to the drumming spot.

3. Birds and windows: Now, you may see cardinals and other birds coming to your window each day and attacking it. You think -- what is that bird doing? The poor bird sees a reflection and thinks it is another bird. Each morning, it wakes up and goes to check the window to see if that pesky rival bird shows up. Sure enough -- it is there each day! So the bird resumes its attacks to drive the competitor away. Sometimes, both males and females will attack their reflections during the breeding season (see these cardinals attacking a window). You can resolve this issue by breaking up the image on the window. Painters tape or any type of material attached to the outside of the window will help break up the image and stop the bird from attacking the window.

4. Mole crickets: You have probably heard mole crickets calling on warm spring/summer nights but did not know what made the sound. Yes, even insect noises -- well, most of them -- are all about sex. These are males calling trying to attract females. Unlike other crickets, male mole crickets sing below ground. They build a horn-like chamber underground with two openings at the soil surface (see link and wait till the end). During construction, males will periodically sing and change parts of the burrow to get it just right!

5. Alligator growls: Now if you live in the South, tis the season for alligator mating rituals. It involves males growling -- see this video and watch the water dance! Very prehistoric! To attract females, males display by head-slapping the water and producing a deep rumbling bellow. Once a male-female pair is formed, they will swim together, touch each other's snouts, and blow bubbles. Mating takes place in the water and when completed, the male disperses and the female is left to search for a place to build her nest.

Female alligators construct nests by mounding up vegetation, sticks, leaves, and mud in a sheltered spot in or near water. Alligator eggs incubate for about 65 days. During this time, the alligator embryos develop and the sex is determined by the temperature at which the eggs were incubated (temperature-dependent sex determination). A temperature of 30 degrees C (86 degrees F) or below produces females and a temperature of 33 degrees C (91.4 degrees F) or higher produces males. In between those temperatures, at 32 degrees C (89.6 degrees F), there is about a 50-50 chance of getting males or females. Many people live in and around alligators -- people need to be aware, see this fact sheet on how to live with alligators.

6. Anoles and dewlaps: Red/orange dewlap displays of brown and green anoles. Bobbing and displaying, particularly brown anoles, these displays are for both females and rival males. To males, it is saying "This is my territory!" To females, it is saying "Look at me! Mate with me!" You can see these displays on screened-in porches, walls, and almost anywhere during the warm months in Florida and elsewhere. The brown anoles are introduced exotic animals whereas green anoles (that can turn brown by the way) are native to Florida and other states in the Southeast.