The emergence of cicadas in Iowa is a highly anticipated event, with different species emerging at various times throughout the year. Iowa’s unique geography, with its mixture of forests, grasslands, and urban areas, creates a diverse environment that supports a wide range of cicada species. Understanding the emergence patterns of these insects can help residents, outdoor enthusiasts, and scientists alike appreciate the complex ecosystems of the state.
One of the most significant factors influencing cicada emergence dates is the species’ life cycle. Periodical cicadas, such as the 13-year and 17-year cicadas, have particularly notable emergences due to their synchronized life cycles. These cicadas spend years underground as nymphs before emerging in massive numbers, a phenomenon that can be both fascinating and overwhelming. On the other hand, annual or non-periodical cicadas emerge every year but in less dramatic numbers.
Here are key emergence dates and periods for various cicada species in Iowa, keeping in mind that weather conditions, particularly temperature and precipitation, can influence these timings:
Early Summer Cicadas (May and June): Some of the earliest Cicadas to emerge in Iowa are often from the genus Tibicen, which can start appearing as early as late May. These early summer cicadas are typically non-periodical and can be heard singing in the trees around late spring and early summer.
Periodical Cicadas (Mid-May to Early June for 13-year cycle, Late May to Early June for 17-year cycle): Iowa is within the range of both the 13-year and 17-year periodical cicada broods. The 13-year cicadas tend to emerge slightly earlier than the 17-year cicadas, but both species emerge when soil temperatures reach approximately 64 degrees Fahrenheit. The exact emergence years and dates can vary, with broods emerging at different times across the state.
Dog-Day Cicadas (July and August): Known for their dog-day cicada nickname, Neotibicen species emerge in the summer, typically in July and August. These are non-periodical cicadas and are among the most common heard during the hottest summer months.
Scissor Grinder Cicadas (Late June to Early August): The Tibicen latinstonii, or the Scissor Grinder Cicada, is another species that emerges during the summer. Their emergence can start as early as late June and continue through early August, depending on environmental conditions.
Linne’s Cicada (July): This species, known as Tibicen linnei, typically emerges in July and can be identified by its distinctive song.
Swamp Cicada (July and August): The Tibicen tibicen, or Swamp Cicada, emerges during the late summer, with its peak usually in July and August.
Annual Cicadas (June to October): Various annual cicada species emerge throughout the summer, with different species peaking at different times. These cicadas are less synchronized in their emergence compared to periodical cicadas but can still produce a significant presence during the warmer months.
Okansan Cicada (June and July): With a distinctive call, the Neotibicen aurifer, or Okansan Cicada, emerges in June and July, adding to the summer’s symphony of insect sounds.
Apache Cicada (July and August): Emerging in the later part of summer, Tibicen apache, or the Apache Cicada, brings another layer of sound to Iowa’s outdoor landscapes.
Walker’s Cicada (August): As one of the later-emerging species, Tibicen walker, or Walker’s Cicada, can be heard in August, marking the end of the summer’s cicada season.
Understanding these emergence patterns not only aids in the appreciation of Iowa’s biodiversity but also highlights the intricate relationships between species, environment, and climate. As the state continues to experience changes in weather patterns and temperature fluctuations, observing these emergence dates can provide valuable insights into the broader ecological health of the region.
What influences the emergence dates of cicadas in Iowa?
+The emergence of cicadas is primarily influenced by soil temperature, reaching about 64 degrees Fahrenheit for periodical cicadas. Weather conditions, such as rainfall and temperature fluctuations, can also impact the exact timing of emergence.
Are all cicadas in Iowa periodical?
+No, not all cicadas in Iowa are periodical. While the state is home to both 13-year and 17-year periodical cicadas, there are also many species of annual or non-periodical cicadas that emerge every year without the dramatic, synchronized emergences of their periodical counterparts.
How can I distinguish between different cicada species in Iowa?
+Distinguishing between cicada species often involves a combination of observing their physical characteristics, such as color and body shape, and listening to their unique songs. Some species are also more active during specific times of the day or in particular habitats, which can aid in identification.
For Iowans and visitors alike, understanding and experiencing the diverse world of cicadas can enrich their connection to the natural world. By recognizing the unique characteristics and emergence patterns of these fascinating insects, individuals can deepen their appreciation for the complex ecosystems that underpin the state’s ecological balance.
