Conservation Evidence: Evidence Data

Collected Evidence: Collected Evidence: Paint wind turbines to increase their visibilityA single ex situ experiment found that thick black stripes running across a wind turbine’s blades made them more conspicuous to an American kestrel than control (unpatterned) blades, but that other designs were less visible, or indistinguishable from controls. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F258https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F258Wed, 18 Jul 2012 13:40:49 +0100Collected Evidence: Collected Evidence: Deter bats from turbines using radar We found no studies that evaluated the effects of deterring bats from wind turbines using radar on bat populations. ‘We found no studies’ means that we have not yet found any studies that have directly evaluated this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F967https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F967Fri, 20 Dec 2013 11:25:11 +0000Collected Evidence: Collected Evidence: Deter bats from turbines using ultrasound Four studies evaluated the effects of deterring bats from wind turbines using ultrasound on bat populations. The four studies were in the USA. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (3 STUDIES) Survival (3 studies): Three replicated, randomized, controlled studies (one with a before-and-after trial in the second year) in the USA found mixed results. In the first year of one study, 21-51% fewer bats were killed at turbines with an ultrasonic deterrent fitted than at control turbines, but in the second year, from 2% more to 64% fewer bats were killed at turbines with ultrasonic deterrents fitted. One study found that using an ultrasonic deterrent emitting a constant or pulsed signal had mixed effects on the fatality rates of three bat species. One study found that using ultrasonic deterrents resulted in fewer fatalities for two of three bat species. BEHAVIOUR (1 STUDY) Behaviour change (1 study): One paired sites study in the USA found fewer bats flying near one of two wind turbines with an ultrasonic deterrent compared to turbines without, but the effect of the deterrent overall was not significant. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F968https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F968Fri, 20 Dec 2013 11:30:12 +0000Collected Evidence: Collected Evidence: Prevent turbine blades from turning at low wind speeds ('feathering') Six studies evaluated the effects of preventing turbine blades from turning at low wind speeds on bat populations. Five studies were in the USA and one was in Canada. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (6 STUDIES) Survival (6 studies): Five of six studies (including five replicated, controlled studies and one before-and-after study) in the USA and Canada found that preventing turbine blades from turning at low wind speeds (‘feathering’), or feathering along with increasing the wind speed at which turbines become operational (‘cut-in speed’) resulted in fewer bat fatalities than at conventionally operated turbines. The other study found that automatically feathering turbine blades at low wind speeds did not reduce bat fatalities. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F970https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F970Fri, 20 Dec 2013 12:19:55 +0000Collected Evidence: Collected Evidence: Automatically reduce turbine blade rotation when bat activity is high Two studies evaluated the effects of automatically reducing turbine blade rotation when bat activity is high on bat populations. One study was in Germany, and one in the USA. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (2 STUDIES) Survival (2 studies): Two replicated studies (one randomized, controlled and one paired sites study) in Germany and the USA found that automatically reducing the rotation speed of wind turbine blades when bat activity is predicted to be high resulted in fewer bat fatalities for all bat species combined and for five bat species. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F971https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F971Fri, 20 Dec 2013 12:34:12 +0000Collected Evidence: Collected Evidence: Increase the wind speed at which turbines become operational (‘cut-in speed’) Twelve studies evaluated the effects of increasing the wind speed at which turbines become operational (‘cut-in speed’) on bat populations. Ten studies were in the USA and two were in Canada. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (12 STUDIES) Survival (12 studies): Ten of 12 studies (including 10 replicated, randomized, controlled studies and one before-and-after study) in the USA and Canada found that increasing the wind speed at which turbines become operational (‘cut-in speed’), or increasing the cut-in speed along with preventing turbine blades from turning at low wind speeds (‘feathering’) resulted in fewer bat fatalities than at conventionally operated turbines. The other two studies found that increasing cut-in speeds did not reduce bat fatalities, but sample sizes were small or treatments were applied for short periods only. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1960https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1960Tue, 04 Dec 2018 15:54:57 +0000Collected Evidence: Collected Evidence: Use acoustic devices to deter marine and freshwater mammals from an area to reduce noise exposure Four studies evaluated the effects of using acoustic devices to deter marine and freshwater mammals from an area to reduce noise exposure. Two studies were in the North Sea (Germany), one study was in the Great Belt (Denmark) and one was in Faxaflói Bay (Iceland). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (4 STUDIES) Behaviour change (4 studies): Three studies (including two controlled and one before-and-after study) in the North Sea and the Great Belt found that using acoustic devices to deter mammals from an area at a wind farm construction site or pelagic sites reduced the activity and sightings of harbour porpoises at distances of 1–18 km from the devices. One before-and-after study in Faxaflói Bay found that when an acoustic device was deployed from a boat, minke whales swam away from the device, increased their swimming speed, and swam more directly. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2896https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2896Mon, 08 Feb 2021 12:04:42 +0000