The effects of investigator disturbance on procellariiform seabirds: A review

Abstract

Despite long-held concerns about the effects of researchers on breeding birds, few studies have focused on the impact of investigators on Procellariiformes. In this review, we summarise published investigations concerning the effects of investigators on physiology, behaviour, reproductive success, offspring quality, and population trends of procellariiform seabirds. Many of the smaller procellariid taxa, such as storm-petrels (Hydrobatidae, and some shearwater Puffinus species) are particularly sensitive to handling during the incubation period, resulting in lowered reproductive success, burrow shifts, and increased divorce between pairs. However, repeated handling of chicks does not seem to have a discernible effect on chick quality. In larger procellariiforms, the presence of researchers within the breeding colony is associated with significant increases in heart rates. Therefore, researchers seeking unbiased estimates of demographic and ecological parameters of birds should be encouraged to measure their own impact and report the findings in the literature, even if they detect no adverse effects of investigator disturbance. Techniques should be developed that ensure the accurate recording of birds' natural behaviour while minimising the impact of investigator disturbance. If investigators are willing to study disturbance problem s, it should be possible to reduce biases caused by their activities.

Apparent survival of adult Leach’s Storm-petrels (Oceanodroma leucorhoa) breeding on Bon Portage Island, Nova Scotia

“…Something to be cognizant of in survival and other CMR studies is investigator disturbance, which can influence reproductive success and potentially lead to nest abandonment (Blackmer et al 2004, Carey 2009but see O'Dwyer et al 2006, Fiske et al 2013. Burrows on Bon Portage Island were visited only twice during incubation, which should be associated with infrequent abandonment (Blackmer et al 2004).…”

Microphone variability and degradation: implications for monitoring programs employing autonomous recording units

“…Furthermore, the ease of obtaining repeat "visits" to the same location can also facilitate the application of statistical methods such as N-mixture modeling (Royle and Nichols 2003) to estimate and account for biases in detection probability. ARUs are well suited to monitor species that are logistically difficult to monitor (e.g., nocturnal species) using human observers (Goyette et al 2011, Rognan et al 2012) and can reduce impacts on wildlife (Carey 2009) as well as potential biases caused by the presence of an observer (Gutzwiller andMarcum 1997, Riffell andRiffell 2002). In addition, recordings have the added benefit of creating a permanent record of the acoustic environment that can be viewed on a spectrogram (Digby et al 2013), listened to multiple times (Haselmayer and Quinn 2000), analyzed by multiple analysts to verify species identifications (Hobson et al 2002), or even slowed down to enumerate certain species based on temporal separation between calls (Drake et al 2016).…”

Behavioral and reproductive effects of bird-borne data logger attachment on Brown Pelicans (Pelecanus occidentalis) on three temporal scales

“…As the effects of both handling and tagging may vary among and within species (Barron et al 2010;Vandenabeele et al 2012), it is important to understand whether and how individual tracking data might be impacted by tag-induced behavioral changes for specific species under study. Moreover, tagging also has the potential to reduce breeding success or increase mortality rates, which are of particular concern in imperiled species (Carey 2009). For example, seabirds are among the most threatened avian taxa globally (Croxall et al 2012), and their limited reproductive output-typically only 1-2 young per year-means that the survival and condition of breeding adults play a crucial role in population dynamics (Fredricksen et al 2008).…”