HISTOPLASMOSIS AND ITS IMPACT ON BLACKBIRD/STARLING ROOST MANAGEMENT

Histoplasmosis is a common and sometimes serious fungal disease that primarily affects the lungs, but can also involve other parts of the human body. The disease is characterized by 3 major forms: acute pulmonary, chronic cavitary, and disseminated histoplasmos is. Two fungicides are effective in treatment of the disease, but serious side effects often result. The occurrence of the fungus, Histoplasma capsulatum, is associated with large quantities of bird and bat excreta that have come in contact with soil. Roost sites must generally be occupied by birds for at least 3 years before soil conditions are conducive to its growth. Once established, the fungus remains for years, but its development can be prevented by bird dispersal and lethal bird control techniques. Infested sites may, with difficulty, be decontaminated using formal in

CONTROLLING BLACKBIRDS AND STARLINGS AT WINTER ROOSTS USING PA-14

The only EPA-registered chemical for lethal control of winter roosting blackbird (Icterinae) and European starling (Sturnus vulgaris) populations is Compound PA-14 Avian Lethal Agent (PA-14). Between 1978 and 1987, 39 PA-14 spray operations, 15 by helicopter and 24 by ground-based spray systems, have been conducted at 33 winter roosts in Kentucky, Tennessee, and Alabama. In-roost bird mortality for the aerial operations have been poor, averaging only 4% of the pretreatment roost populations or 114,000 birds killed per spray operation. Although very labor-intensive, a ground-based sprinkler system application method has proven much more successful, averaging 67% in-roost bird mortality for 17 spray operations or 287,000 birds killed per operation. A much less labor-intensive ground-based spray system using a pivotal water cannon and chemical injector pump is presently being developed and tested. Results of 7 test sprays conducted in 1986 and 1987 showed an average 57% in-roost bird mortality (203,000 birds killed per spray operation) and investigations into the bird control uses and limitations of this system are continuing

DRC-6749--AN AVIAN WETTING AGENT OF LOW AQUATIC TOXICITY

PA-14, the compound presently registered for lethal control of blackbirds and starlings at roosts, is labelled for use only at upland sites. Research was undertaken to identify another wetting agent which might be registered for use at aquatic sites. Of 90 samples received from suppliers, 60 were evaluated for wetting ability in a standard laboratory test. Of these, 10 were chosen for test against an aquatic indicator animal, Daphnia. One of the 10, DRC-6749, a block copolymer, was found significantly low in toxicity, and underwent further aquatic testing against 6 fish and 1 mussel species. Under standard test conditions, no fish mortality occurred at concentrations up to 2,000 mg/1. Some fish mortality occurred at higher temperatures: for rainbow trout at 17 C and bluegills at 22°C were 801 and 740 mg/1 respectively. No mussel mortality occurred at these temperatures with concentrations up to 2,000 mg/1. Laboratory spray tests showed that DRC-6749 solutions were capable of wetting birds at reasonable application rates, and a field trial confirmed this with an estimated kill of 63,200 blackbirds and starlings from an application of 208 1 of DRC-6749 and 2.3 cm of water over a 0.46 ha area

DECONTAMINATION OF A HISTOPLASMA CAPSULATUM-INFESTED BLACKBIRD ROOST: USE OF A SPRINKLER SYSTEM TO APPLY FORMALIN

When disturbed, blackbird/ starling roost sites can be sources of locally severe outbreaks of histoplasmosis; therefore decontamination with formalin is sometimes prudent. We describe the use of a $5000 sprinkler system for spraying formalin on a Histoplasma capsulatum-infested roost site. This system precludes direct worker involvement in the application of this hazardous chemical to the area. Analysis of soil samples collected and cultured both before and after formalin treatment confirmed the eradication of H. capsulatum from the 1.3 ha site. Cost was approximately$17,000 with sprinkler system provided at no charge