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.

Abstract. Pollution of the world's oceans affects a wide variety of marine organisms and raises major conservation concerns. Ingestion of plastic debris has increased since the 1970s, particularly among the Procellariiformes, resulting in a range of lethal and sub-lethal side effects. Plastic loads (grams of plastic per bird) of adult Short-tailed Shearwaters (Ardenna tenuirostris) are well known from research in the northern hemisphere, but the amount of plastic ingested by their offspring has yet to be quantified. In this study, the stomach contents of fledgling Short-tailed Shearwaters on Phillip Island, Victoria, were analysed for plastic particles. All birds sampled contained plastic, averaging 7.6 particles per bird. The mean mass of plastic per bird was 113 mg. The most common type of plastic was user plastic, followed by industrial pellets. The birds contained a small proportion of other refuse, such as polystyrene and plastic bag. Plastics were primarily light in colour, though red and grey-black materials were also recorded. Despite a weak trend, no clear influence of ingested plastic on body condition could be demonstrated, although there was some evidence of physical damage to the gizzard. Accumulation of plastic objects in the digestive tract over time may indirectly affect the life cycle of species and their reproductive success, with long-term harm caused to populations. Data suggests that an assessment of the effect of this type of pollution on seabird welfare is urgently required.

No abstract

Research procedures can have a detrimental effect on the reproductive success of the study species. In this study, the frequency of investigator disturbance on Short‐tailed Shearwaters Puffinus tenuirostris was examined experimentally throughout the incubation period to assess whether disturbance influences hatching success, pre‐fledging chick survival and chick body size. Handling of incubating birds every day, every 3 days and once a week reduced hatching success by 100, 61 and 39%, respectively, compared with pairs that were not disturbed. Most failures resulted from egg abandonment by the parents, particularly during the early stage of incubation. Chick survival did not differ between treatment groups, but control chicks were significantly heavier and had larger bill depths and longer wings. The difference in chick body mass and size observed between the control and disturbed chicks might be due to physiological or behavioural mechanisms in adults or carry‐over effects from the incubation stage to the next life‐history stage. Reduced offspring quality has the potential to affect post‐fledging survival and recruitment. These findings are significant in broader terms because any investigator disturbance that reduces reproductive success, survival and offspring fitness could interfere with the accurate assessment of demographic parameters and exacerbate population declines.

Migratory marine species cross political borders and enter the high seas, where the lack of an effective global management framework for biodiversity leaves them vulnerable to threats. Here, we combine 10,108 tracks from 5775 individual birds at 87 sites with data on breeding population sizes to estimate the relative year-round importance of national jurisdictions and high seas areas for 39 species of albatrosses and large petrels. Populations from every country made extensive use of the high seas, indicating the stake each country has in the management of biodiversity in international waters. We quantified the links among national populations of these threatened seabirds and the regional fisheries management organizations (RFMOs) which regulate fishing in the high seas. This work makes explicit the relative responsibilities that each country and RFMO has for the management of shared biodiversity, providing invaluable information for the conservation and management of migratory species in the marine realm.