Cicindela hirticollis rhodensis    Calder, 1916

Hairy-necked Tiger Beetle 


MN Status:
endangered
Federal Status:
none
CITES:
none
USFS:
none

Group:
insect
Class:
Insecta
Order:
Coleoptera
Family:
Cicindelidae
Habitats:

(Mouse over a habitat for definition)


Cicindela hirticollis rhodensis

Click to enlarge


Map Interpretation

Map Interpretation

  Synonyms

  Basis for Listing

The Hairy-necked Tiger Beetle (Cicindela hirticollis ssp. rhodensis) was first observed in Minnesota in 1960 at two locations along the Lake Superior shoreline near Duluth in St. Louis County (North Shore Highlands Subsection), which represents the western periphery of the subspecies range. It was verified in this area on several occasions until 1974.  In 1996, the Hairy-necked Tiger Beetle was listed as a species of special concern. No further efforts to document the species were made until it was relocated at one of the two original collection sites in 2003. Habitat loss to development and recreational use of beach habitats has been ongoing in this area, potentially threatening the last known site. Given its restricted distribution and the vulnerability of its habitat, the status of the Hairy-necked Tiger Beetle (ssp. rhodensis) was elevated to endangered in 2013.

  Description

Adult Hairy-necked Tiger Beetles average 10-15 mm (0.39-0.59 in.) in length and are dull brown to reddish brown in color.  When they are freshly emerged in the fall, they have a very "hairy" thorax.  The "hairs" are abraded and lost after overwintering underground and then experience further wear the following spring and summer. At that time, the Hairy-necked Tiger Beetle can be confused with the smaller (10-13 mm (0.39-0.51 in.)) and extremely abundant Bronzed Tiger Beetle (Cicindela repanda); however, the posterior tips of the wing covers are more pointed in C. hirticollis, versus more rounded in C. repanda.

Tiger beetle larvae are mostly white and somewhat grub-like (Pearson et al. 2015). The portions of their bodies that are exposed in their burrow entrances are usually the same color and texture as the surrounding soil surface, allowing them to blend in with the soil (Pearson et al. 2015; R. Dana, Minnesota DNR, personal communication). Tiger beetle larvae have eyes with dense photoreceptors that give them detailed focusing ability and three-dimensional visual perception (Pearson et al. 2015).

  Habitat

The Hairy-necked Tiger Beetle (ssp. rhodensis) is only known from sandy beaches along the Lake Superior shoreline near Duluth. Other subspecies of the Hairy-necked Tiger Beetle found in Minnesota are known from sandy lakeshores and large sandy river systems away from Lake Superior.

  Biology / Life History

Adults of this species may emerge in the fall, feed until cold weather, and then burrow underground for the winter. Some individuals may also overwinter as larvae (Pearson et al. 2015). Adults emerge the following spring and begin feeding, mating, and laying eggs. They slowly die off as the season progresses.

Tiger beetles prey on small insects and other arthropods and are visual hunters. Adults will either chase their prey or wait in a shaded area and ambush prey as it wanders by (Pearson et al. 2015). They often chase their prey in fast, short bursts, with brief stops in between runs. These stops are necessary for orientation, as tiger beetles can run so fast that they cannot see the prey they are pursuing.

Adults have hind wings that are transparent, and they are folded under the elytra (hard front wings) when at rest. When disturbed, tiger beetles may take short, low flights to escape. These escape flights, and the ability to run quickly, are their main defenses against predators. Tiger beetles are also usually well camouflaged in their environment.

Tiger beetle larvae dig burrows in which they live and secure prey. The burrows of the Hairy-necked Tiger Beetle are vertical and constructed at the back of the beach, away from the water line but where the sand is still moist. Tiger beetles are ambush predators that lie in wait at the top of their burrows, with their jaws open and their heads and thorax flush with the ground surface, essentially filling the burrow entrance and disguising their presence (Pearson et al. 2015). When prey is within reach, the larvae anchor themselves to the sides of the burrow by two pairs of hooks on their lower backs and quickly leap out and grab the prey with their mandibles. The struggling prey is then pulled back into the bottom of the burrow and eaten. When they are done eating, the larvae carry the indigestible portions of the prey to the top of their burrow and throw it backwards, away from the burrow entrance. The larvae also use their burrow for protection and will retreat into it when they sense danger. Larvae primarily use vision to detect danger, but may also sense vibrations in the ground created by large predators. Burrow depth is 8-20 cm (3.1-7.9 in; Pearson et al. 2015).

  Conservation / Management

Many subspecies of Cicindela hirticollis are in decline, with at least one believed to be extinct, and human-caused changes to habitats are widely implicated (Knisley and Fenster 2005). Because the Hairy-necked Tiger Beetle (ssp. rhodensis) is known to occur in Minnesota in only a small area of lakeshore, it is extremely vulnerable to development, off-road vehicle use, and foot traffic on the beach. Pollution, shoreline riprap, and other shoreline modifications also threaten the continued existence of this species in Minnesota. The increased frequency of heavy rains and associated flooding that result from climate change may affect larval survival (Brust et al. 2005). Loss of genetic diversity due to isolation is also a possible risk factor for this species. As a whole, the Hairy-necked Tiger Beetle seems vulnerable to human disturbance throughout its range and has been in decline in many areas (Graves et al. 1988).

  Conservation Efforts in Minnesota

A better understanding of the distribution and abundance of the Hairy-necked Tiger Beetle along Lake Superior is needed. Existing populations need to be protected from excessive recreational beach use with fencing. Experimental creation of sandy habitat adjacent to existing populations should be considered.

  Authors/Revisions

Ronald L. Huber, 2008; Christopher E. Smith, 2017

  References

Casey, T. L. 1916. Further studies in the Cicindelidae. Memoirs on the Coleoptera, VII. The New Era Printing Co., Lancaster 34 pp.

Coffin, B., and L. Pfannmuller, editors. 1988. Minnesota's endangered flora and fauna. University of Minnesota Press, Minneapolis. 473 pp.

Freitag, R. 1999. Catalogue of the tiger beetles of Canada and the United States. NRC Research Press, Ottawa, Ontario, Canada. E-book.

Graves, R. C. 1988. Geographic distribution of the North American tiger beetle Cicindela hirticollis Say. Cicindela 20(1)1-21.

Graves, R. C., M. E. Krejci, and A. C. F. Graves. 1988. Geographic variation in the North American tiger beetle, Cicindela hirticollis Say, with a description of five new subspecies (Coleoptera: Cicindelidae). The Canadian Entomologist 120(7):647-678.

Knisley, C. B., and M. S. Fenster. 2005. Apparent extinction of the tiger beetle, Cicindela hirticollis abrupta (Coleoptera: Carabidae: Cicindelinae). The Coleopterists Bulletin 59(4):451-458.

Leonard, J. G., and R. T. Bell. 1999. Northeastern tiger beetles. A field guide to tiger beetles of New England and Eastern Canada. CRC Press, Boca Raton, Florida. 176 pp.

Minnesota Department of Natural Resources. 2003. Field guide to the native plant communities of Minnesota: the Laurentian mixed forest province. Ecological Land Classification Program, Minnesota County Biological Survey, and Natural Heritage and Nongame Research Program. Minnesota Department of Natural Resources, St. Paul, Minnesota. 352 pp.

Pearson, D. L., C. B. Knisley, D. P. Duran, and C. J. Kazilek. 2015. A field guide to the tiger beetles of the United States and Canada: identification, natural history, and distribution of the Cicindelinae. Second edition. Oxford University Press, New York, New York. 251 pp. + plates.

Steffens, W. P. 2004. Surveys for Tiger Beetles: Cicindela hirticollis rhodensis. Report to Minnesota Department of Natural Resources. 4 pp.

Steffens, W. P. 2009. Update on the status of Cicindela hirticollis rhodensis habitat in Minnesota. Submitted to Minnesota Department of Natual Resources. 6pp.