Managing the Hooded Plover in Victoria

Appendix 1 Detailed summaries of latest research findings Responses of Incubating Hooded Plovers ( Thinornis rubricollis ) to Disturbance Weston and Elgar (2007) found the most common response to an approaching stimulus involved leaving the nest for a period of time (an ‘‘absence’’): 90.9% of encounters that caused a response (n = 580) resulted in an absence from the nest. Disturbance-initiated absences were significantly more frequent (1.1 ± 1.1 per hour) than incubator-initiated absences (i.e. when the birds take a break from the nest 0.5 ± 0.5 per hour). Overall, nests encountered 3.0 ± 4.2 stimuli per hour (n = 49 observation days; 555 observation hours). The hourly rate of encounters with human stimuli was 2.4 ± 4.0 per hour (maximum 24.2); the rate of encounters with natural stimuli was 0.7 ± 0.9 per hour (maximum 3.5). Only one observation day involved no encounters with natural or human stimuli (2.0% of observation days). This reveals that human encounters are common for incubating Hooded Plovers. Overall, 75.7% of all stimuli were due to humans or their companion animals, and 24.3% involved natural stimuli (n = 1821). Of all encounters, 73.3% involved humans on foot. Within this category, walkers without dogs were the most frequently encountered stimulus at nests, and they accounted for about half of all encounters. Humans were responsible for more time off the nest (33.1%) than any other source, and 68.0% of time off nests was caused by external stimuli. There was a lower than expected frequency of nest absences in response to walkers without dogs and higher than expected absence frequencies in response to magpies and ravens. Research around the world shows that habituation is promoted by stimuli that do not represent any real threat to the birds. Walkers without dogs may be less threatening than other stimuli because they are slow moving, do not persecute the birds, and occur frequently. Ravens and magpies on the other hand have been found to be major predators of Hooded Plover nests (see study by Renee Mead below using remote cameras to detect nest fates). The observed percentage of nest absences in response to encounters with leashed dogs is lower than expected, but the observed percentage of nest absences in response to encounters with unleashed dogs is higher than expected. The percentage of encounters with leashed dogs that caused an absence from the nest was similar to the percentage of 202 encounters with walkers without dogs that caused an absence (ca. 21%). This suggests that it is the behaviour of dogs rather than their presence that influences whether nest absences occur. The particularly disturbing nature of unleashed dogs is probably explained by their tendency to move up and down the beach perpendicular to the water’s edge (see Burger 1986). Additionally, unleashed dogs directly pursued Hooded Plovers at times. About 17% of encounters with potential causes of disturbance occurred while birds were already responding to other disturbance, and this prolonged the return to the nest. Humans occurred predominantly in the midbeach: 71.7% of 2361 people who passed nests were in the midbeach. This means that nests in different habitats (beach, foredune, dunes) may be differentially affected by human disturbance. Weston and Elgar (2007) found that encounters at beach and foredune nests were more likely to result in incubator absences, and that the duration of absences at foredune nests was longer than for dune or beach nests. The incubating birds on beach and foredune nests are not only closer to the approaching ‘threat’ but have a clearer view of approaching threats, which may explain the greater tendency of birds to respond to these approaching threats. Disturbance to brood-rearing Hooded Plover Thinornis rubricollis: responses and consequences Weston and Elgar (2005a) examined the causes and consequences of disturbance to the chicks of Hooded Plover. Disturbance might cause thermal stress to chicks. Hooded Plover chicks are expected to have difficulty maintaining their body temperature without parental assistance, and disruption of brooding is likely to interfere with thermoregulation. Of 261 brooding bouts recorded, 44.8% ended because of disturbance. Almost a third (31.0%) of all brooding bouts observed were ended by an encounter with a human. Chicks found themselves un- brooded due to disturbance for up to 290 min, and in ambient temperatures of 10–46°C. Disturbance might cause energetic stress to chicks. Encounters with humans usually caused chick foraging to stop. Higher levels of disturbance were associated with less chick foraging. There was a tendency for broods to forage in lower and potentially more 203 profitable levels of the habitat in less-disturbed conditions. However, the overall pattern of habitat use was similar during disturbed and less-disturbed conditions. Adult defence of broods could be compromised by disturbance. However, no brood predation occurred in disturbed circumstances, and adults stayed close to their broods even in disturbed conditions. The main source of encounters with Hooded Plover broods were humans (81.1% of encounters). The main response of chicks is to run to foredunes and dunes to hide. The heavy reliance of Hooded Plover chicks on the dunes and foredunes as the main site of concealment emphasizes the importance of dune systems in the habitat of this species. This study can offer no unequivocal evidence linking levels of disturbance with reduced chick survival in Hooded Plover. Nevertheless, the data reveal that disturbance reduces feeding and disrupts brooding of chicks, influences that might reduce chick survival. Reduced foraging and brooding due to disturbance are thought to be responsible for decreased chick survival in the ecologically and behaviourally similar Piping Plover Charadrius melodus . Effectiveness of signed and fenced areas for reducing nest crushing and disturbance to Hooded Plovers Weston et al. (2012a) explored whether three types of nest protection scenarios referred to as Temporary Beach Closures (TBC) (signage; signage and temporary fencing, and; signage, temporary fencing and wardening) differed in their conferred benefit to Hooded Plovers measured as (1) achieving compliance among beach visitors, and (2) reducing egg-crushing rates. Overall, 93.7% of beach visitors complied with TBC, resulting in a reduction in egg- crushing rates within (3.9% of eggs were crushed), as opposed to adjacent to, the protected areas. Levels of compliance were high in all three TBCs (88.0–99.4%), and similar levels of compliance were achieved within the three scenarios. Human compliance was highest for females and when the density of beach-users was higher (particularly in the middle of the day between 12pm and 2pm), while individuals aged <20 and >61 years were less likely to comply with nest protection scenarios. Despite an increased 204 probability of compliance on high density beaches, this did not translate into a reduction in egg crushing rates on such beaches, because the overall number of non-compliant individuals remained higher. The finding that compliance was highest for nest protection efforts at beaches with higher encounter rates and during busier times of the day (i.e. the middle of the day) highlights the strong role of social norms in influencing compliance (Manfredo and Dayer 2004; Williams et al. 2009). It may also be in part to the dichotomy in user groups visiting beaches (Maguire et al. 2011a), where visitors (non-local residents) are more likely to visit the beach in the middle of the day, and in this study, perhaps be more receptive and compliant with signage. Weston et al. (2012a) concluded that nest protection efforts are meritorious, and that their use on high and low-use recreational beaches will benefit breeding shorebirds by reducing the rate of egg-crushing. Targeting demographics that display lower levels of compliance, such as men, young people (i.e. <21), and older people (i.e. >60), may further improve the effectiveness of nest protection efforts. Nest Return Times in Response to Static Versus Mobile Human Disturbance Weston et al. (2011) delivered standardized stimuli to incubating Hooded Plovers to examine the influence of human movement on disruption of incubation classified as mobile (activities moving past the area e.g. walking, jogging) or static (activities stationed within the one area e.g., sunbathers, anglers, and picnickers). Observations across 82 days during the breeding season revealed 7,217 humans on breeding territories, of which 63.5% were classified as static. Results indicated that static humans caused substantial disruption to incubation that almost always exceeded 60 min (19 of 20 pairs), regardless of nesting habitat. The probability of plovers returning to nests within 60 min was higher in the treatment that mimicked mobile (e.g., walking) humans (85.7%) than in the treatment that mimicked static (e.g., sunbathing) humans (9.5%; n = 20 pairs). Thus, temporary beach closures (i.e. nest protection signage/fencing) that reduce or eliminate static but not mobile disturbances are likely to be effective at reducing disruption to incubation caused by human disturbance. 205 Sign content and placement Threatened species signage is frequently used to help protect species by limiting human occurrence or alter damaging human behaviour, yet is rarely developed using a scientific approach which involves collecting data from the key target audience in regard to their preferences for signs and placement of signs. Rimmer et al. (2013) surveyed members of the beach-going public (n = 684) to document their preferences for desirable features and positioning of signage to protect threatened beach-nesting birds. Respondents were ‘likely’ to read a sign that was positioned on or near the beach (4.39 ± 0.03, where 1 and 5 were “definitely not” and “definitely” respectively; n = 516). When asked where signs should be placed to be highly ‘noticeable’, 78.4% of 524 respondents believed signs should be placed at the beginning of an access path, 62.2% in the carpark, 59.0% on the upper beach, 58.6% at the beach end of the access path, 36.1% on the dune, and 26.5% on the lower beach.

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