Ave Maria University Student Documents Changes in Insect Populations Following Development

Insects are critically important to our world: They bolster the global food supply through pollination, recycle organic waste, support food webs that sustain countless species, and more. Yet they are largely in trouble due to the impacts of urbanization, especially habitat loss, pesticide use, and light pollution.

Over the past three years, Ave Maria University student Zachary Lang, working under the supervision of Dr. Tirado, studied the number of species and individual insects in the master-planned community of Ave Maria to create a baseline of data that could be referenced for detecting future changes to insect populations as they respond to continued development and other impacts. Because of its relatively undisturbed landscape and proximity to the burgeoning community, Corkscrew Swamp Sanctuary was the perfect “control” or comparison site for the light-trapping aspect of his study.

Why study insects here?

In 2005, construction of the Ave Maria community and university began, largely on farmland that became overrun with invasive plants after it was left abandoned for several years. Disturbed environments like Ave Maria remain poorly documented relative to more intact systems. Because this highly disturbed landscape hosts a well-established invasive plant community, Lang wanted to find out if it still provides good habitat for insects.

Collecting baseline data about insects in these habitats is critical for detecting future changes in species richness and community structure, particularly in response to continued development.

Light trapping and more

Insect activity increases by 30% at night, particularly in wetlands. Because insects are attracted to artificial lights, Lang studied them using a variety of methods, with a focus on light trapping. Using lights to attract insects can reveal rare or undescribed insects typically not encountered by other methods. Lang used 7-watt UV bulbs hung from a rope with white sheets or placed inside a mesh enclosure on which insects could land. He also used a 250W mercury vapor bulb, which is considered the best for attracting insects due to its intensity and broad wavelength range. The mercury vapor bulb was placed on a tripod on top of white sheets spread on the ground.

In addition to light trapping at both locations, Lang also conducted general field searches, sweep netting, baiting, and soil sieving on and around campus. He conducted this work during the school semesters from 2023 through 2026, sampling a variety of Ave Maria’s habitats, such as roadside vegetation, stormwater canals, and retention ponds.

Three years of insect data

Over three years, Lang photographed and identified more than 4,300 individual insects representing 655 species. The specimens encompassed 188 families in 17 insect orders, with 250 different species of Lepidoptera, which are butterflies and moths. The next order with the greatest variety was Coleoptera (beetles), with 131 different species.

Rather than studying insect abundance, Lang focused on the diversity, or different types of insects, present in each habitat. Generally, greater plant diversity in a habitat will lead to greater insect diversity. This is because plants provide food, shelter, breeding sites, and environmental conditions that insects need to survive.

During only two sample nights conducted at the Sanctuary “control” site, Lang recorded 191 species; 27 of which were unique to Corkscrew Swamp Sanctuary. This is remarkable because Lang sampled dozens of times at Ave Maria. While insects are more active during warm and humid nights with a dark sky, season and time of night also affect sampling results. Lang says that species present can tell us about environmental conditions and habitat type, and with more sampling, there is likely to be a larger variety of species. Additionally, the habitat at the Sanctuary likely harbors greater insect diversity as it is omitted from regional mosquito control efforts.

More than 500 of the insects were pinned and labeled for preservation and educational use at Ave Maria University. Lang hopes that future students will continue the survey at Ave Maria to see how the insect populations continue to change as the community expands, and a native plant garden is installed.

Highlights from sampling at Corkscrew Swamp Sanctuary? Lang was most excited to see a jeweled satyr moth.

Why is this important?

Many of the insect species recorded around Ave Maria are also found in similar habitats at the Sanctuary, so this data contributes to Audubon’s knowledge of existing insect populations. This is particularly helpful as climate change impacts bird habitat and food sources. To combat these threats on a large scale, Audubon is raising our sights and our impact across the full length and breadth of the hemisphere—both the migratory pathways of today and the refuges birds will seek out as climate change progresses.

As the benefits of Audubon’s visiting scientist program are far-reaching, a highlight of Audubon’s upcoming campus improvements at the Sanctuary is a new research laboratory, in addition to office and dormitory space to support visiting researchers. While helping inspire the next generation of biologists, research partners like Ave Maria University —through the mentorship and supervision of faculty such as Dr. Tirado—are vital for filling gaps in our knowledge of Corkscrew Swamp Sanctuary’s ecology, demonstrating the value of conservation lands in a developing landscape, and helping measure environmental change across our region.