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Life After Water Series: Life of the True Bug

Life of the True Bug: a lesson in walking on water

The true bug is a fascinating benthic macroinvertebrate that will undergo incomplete metamorphosis involving the following phases: the egg, the nymph stage, and the adult stage. Today we will explore what happens after the true bug leaves the safety and familiarity of the water. And how does the true bug transform into its adult form? To explore these questions, we’ll start at the very beginning—when the true bug eggs are first laid.

The life cycle of a true bug varies and can take anywhere from just a few weeks to over 17 years. When mating occurs, the male will ride the back of the female and join the tips of both their abdomens where he will deposit his sperm into the reproductive organs of the female. The fertilized egg will be deposited by the female either on plant material, soil or bark and will hatch in about four weeks’ time.

After hatching from the eggs, the true bugs will enter their nymphal stage in which they will grow in size while going through a series of 5 developmental stages (called instars), shedding their exoskeletons also known as moutling. As they are developing and growing in size, they also develop wing pads and scent glands for protection. At this stage, nymphal true bugs bear a similar resemblance to their adult equals, however they are smaller in size. Nymphal development will occur rapidly throughout the summer months so that true bugs will be ready to mature and go into their adult phase before winter.

As an adult, the true bug may choose to either remain active throughout the winter months or hibernate over winter. In areas where ponds freeze over, the adults of many species of true bugs may fly to streams where the water does not freeze for the winter. Mating will typically occur during the spring time and continue throughout early summer. True bugs will engage in a courtship period prior to mating that is short and includes a variety of the following: vibrations, sounds, the flashing of brightly coloured legs, wings, antennae and the production of special chemicals called pheromones that are used to attract mates.

True bugs can be split into three main groups; the fully aquatic group, the surface skaters and the shore bugs. The fully aquatic group involves 6 families of hemipterans that are fully aquatic in all its life history stages. The surface skaters involve 4 families that are semi-aquatic, having life stages both in water and on land. Lastly, the shore bugs involve 4 families and they live along the edges of ponds and streams throughout their life stages.

Fun Fact: Although most true bugs have poorly developed flight muscles, on occasion a true bug may still fly to a different pond, stream or river for the purpose of colonizing that water body.

Fun Fact: The attraction between water molecules on the surface of a water body  creates tension and a delicate membrane. Water striders, a type of true bug, have tiny hairs on their legs that repel water and capture air allowing them to stride across the surface of water bodies. The captured air allows them to float and move about more easily.

Interested in learning more about benthic macroinvertebrates and how they can be used to measure the health of rivers and streams? Be sure to follow EcoSpark’s social media to stay updated on our Changing Currents program and our other citizen science and environmental education programs.


References

The National Wildlife Federation. (2018). Water Striders. Retrieved from: https://www.nwf.org/Educational-Resources/Wildlife-Guide/Invertebrates/Water-Striders


Carina holds a Bachelor of Honors in Environmental Studies and a diploma in Ecosystem Technology, both of which developed her interest in using geographic information systems to communicate about complex issues, such as climate change. In her role as Lead Environmental Educator, Carina designs geospatial education tools for EcoSpark’s citizen science programs. When outdoors in the field, you will often find her streamside identifying aquatic critters, communicating her enthusiasm for the outdoors, and demonstrating her dedication to stewardship practices with youth and adults throughout the GTA.