Brooksville Bellflower

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Brooksville Bellflower

Campanula robinsiae

Status	Endangered
Listed	July 27, 1989
Family	Campanulaceae (Bellflower)
Description	Solitary annual herb with deep purple, bell-shaped flowers.
Habitat	Moist pond margins.
Threats	Residential and agricultural development.
Range	Florida

Description

Brooksville bellflower, Campanula robinsiae, is a small annual herb that grows up to 6 in (15 cm) tall and bears deep purple, bell-shaped flowers about 2.5 in (1 cm) wide. Leaves are ovate to elliptical and are larger near the base. Many of the flowers are inconspicuous, being closed and self-pollinating. Others are solitary, open and cross-pollinating. The open flowers consist of a sepal 0.04-0.1 in (1-2.5 mm) long and a bell-shaped corolla, about 0.28-0.31 in (7-8 mm) wide. Flowering is in March and April.

The only other bellflower in Florida, C. floridana, is widespread, and can be distinguished by its shorter sepals and longer corolla.

This species, which was first described in 1926, was previously considered an introduced Eurasian species. However, it has now been shown to be a native, narrowly endemic species.

Habitat

The Brooksville bellflower was first discovered on the moist north slope of a hill. Field work in the 1980s showed that the species was primarily found on moist ground at the edges of two nearby ponds. Due to its rarity, any habitat alteration, such as unnatural fluctuations in water level or quality, could be disastrous.

Distribution

This bellflower is known only from three sites in Hernando County, north of Tampa, Florida. One site is the discovery site on Chinsegut Hill; two larger sites are at the margins of nearby ponds.

One of the sites in Hernando County is on land owned by the U.S. Department of Agriculture, one is a tract administered by the Florida Game and Fresh Water Fish Commission, and the third population at Lake Lindsey is under private ownership. The ponds that support the main populations are subject to seasonally fluctuating water levels, which determine the plant's year to year abundance.

Threats

The main threat to the species, apart from unintentional mismanagement of known sites, may be from changes in quality or quantity of surrounding watersheds, which may be contaminated by petroleum products, fertilizers, and herbicides. Because it is so small and short-lived, the Brooksville bell-flower may be easily overlooked, and for this reason biologists hope that further searches might reveal additional sites harboring the species.

The Hernando County development boom of the 1980s and 1990s (according to the Census Bureau it was the second fastest-growing county in the nation from 1980 to 1986, growing by almost 75 percent) is also cause for concern; further development, such as a planned Tampa-Jacksonville corridor toll road (which would pass west of Brooksville), would only enhance the threat from construction and community growth.

Conservation and Recovery

The main populations of Brooksville bellflower are not apparently in danger of destruction of their habitat. Plants occur on a U.S. Department of Agriculture (USDA) research station and on protected state land, although the recent spread of rapidly proliferating, exotic plant species, especially the skunk vine (Paederia foetida ) at the USDA tract at Chinsegut Hill, are considered a growing threat.

The 1994 recovery plan from the U. S. Fish and Wildlife Service, which describes necessary efforts to restore both the Brooksville bellflower and the Cooley's water-willow, notes that the primary objective for the plan is the eventual delisting of both species. The plan notes, however, that there is a fundamental lack of basic biological (i.e., distributional, ecological, reproductive, and systemic) knowledge about these species, which makes it difficult to set criteria to determine the time-frame or ultimate likelihood of delisting. Still, the plan states that delisting of both species should become feasible as habitat is protected and new populations are established or old ones reestablished.

According to the 1994 plan, plausible criteria for recovery might include securing at least 10 viable and self-sustaining populations of Brooksville bellflower in pond margin habitats, consisting of approximately 10,000 individuals during prolific years. The major recovery actions outlined in the plan include the development of management and protection criteria for populations on current managed areas; the acquisition of additional habitat, or protection of habitat through conservation easements and/or regulation; the completion of additional surveys to locate new populations; the augmentation of existing cultivated populations, including the establishment of a germ plasm bank; and the development of plans for possible introduction or reintroduction of plants into sustainable habitat.