The regal fritillary (Speyeria idalia) is a striking nymphalid butterfly found among some of the remaining tallgrass and mixed-grass prairies in the east-central United States.

This prairie-specialist butterfly has a characteristic deep orange color and unmistakable dark hindwings with two bands of spots (Brock 2003).

Milkweeds, thistles, coneflowers, blazing-stars, bergamots, clovers, goldenrods, and ironweeds are some of the most important nectar sources for adult regal fritillaries.

The life cycle of the regal fritillary is unique and is thought to be an adaptation to the phenology, or seasonal timing and nature, of their larval food plant, the violet (Kopper et al. 2001).

The fact that the violets remain unable to support larvae throughout the rest of the summer helps to explain the regal fritillary's univoltine life cycle.

The larval diapause coupled with the adult female reproductive diapuase enables the larvae to maximize the benefits of fresh and abundant violet foliage when they are active in the spring (Kopper et al. 2001).

With a loss of more than 99% of the original native tallgrass prairie landcover today (Powell et al. 2006), decreased sustainable habitat area for the regal fritillary has become a real threat.

These populations have been located east of Indiana: Fort Indiantown Gap Pennsylvania, Radford Army Ammunition Plant in Virginia.

The regal fritillary is not federally listed as an endangered species, but it has been assigned a NatureServe conservation status of G3, which is considered vulnerable (Selby 2007).

Since regal fritillaries require relatively non-degraded native tallgrass and mixed-grass prairies, the alteration of these landscapes has pushed them into a highly vulnerable status (Selby 2007).

Largely due to the loss and degradation of the tallgrass prairie landscape, violet plant density tends to be limited or greatly reduced in certain areas.

A study conducted by Kelly and Debinski (1998) looked at larval food source limitations as a factor in the declining regal fritillary populations.

There is an increased likelihood of population extirpation among high gene flow species experiencing habitat fragmentation (Williams et al. 2003).

Prescribed burns have also become a popular low-cost alternative for removing woody vegetation on rural and agricultural lands (Powell et al. 2006).

First instar larvae are highly sensitive to extreme weather conditions as they overwinter in the leaf litter and as they begin their search for food plants in the spring.

Hard frosts late in the spring, severe storms, and cool damp conditions have all been shown to negatively impact larvae survival (Selby 2007).

Therefore, unusually cool conditions in the spring can drastically slow larval growth rates, increasing their exposure to mortality factors (Selby 2007).

Prolonged periods of cooler temperatures, cloudy skies, and rain can restrict normal activities, perhaps limiting reproduction (Selby 2007).

It is thought that the gypsy moth control programs used in the east along wooded grassland edges may have been a final factor leading to the loss of some populations (Selby 2007).

Broadcast spraying of insecticides for pest control on adjacent crop land and rangeland continues to be a direct threat to the regal fritillary.

Land management practices should focus on the maintenance of intact native prairie remnants and the vegetation that is crucial to the regal fritillary's continued survival.

It has been suggested that proper management practices could play a crucial role in slowing, and possibly even reversing, the current wave of regal fritillary extirpations (Swengel 2004).

Connectivity between regal fritillary habitats is extremely important to consider in land management practices and would likely increase gene flow and genetic diversity in certain areas.

Fire management also helps to remove cool season exotics and woody vegetation that encroach on native prairie plants such as the violet.

These practices would likely minimize the negative effects of fire management on regal fritillary populations, while likely providing them with some increased benefits due to higher quality food and nectar resources.

It has also been suggested that very light grazing is also beneficial to these prairie specialist butterflies and can effectively be used in combination with limited prescribed burning (Selby 2007).

However, the use of herbicide on prairie lands should be a last resort to removing unwanted vegetation in order to protect regal fritillary populations (Selby 2007).

Since there is limited knowledge about the exact distribution and abundance of many regal fritillary populations, it is crucial that inventory and monitoring practices are carried out.