Corrigendum: Distilling Professional Opinion to Gauge Vulnerability of Guam Avifauna to Brown Treesnake Predation

A Corrigendum on
Distilling Professional Opinion to Gauge Vulnerability of Guam Avifauna to Brown Treesnake Predation

by McElderry, R. M., Paxton, E. H., Nguyen, A. V., and Siers, S. R. (2021). Front. Conserv. Sci. 2:683964. doi: 10.3389/fcosc.2021.683964

In the original article, there was an error. Unauthorized personal communications and statements were included within the article, which should have been removed. This affects the Results and Discussion sections.

A correction has been made to Results, What Is the Risk of Death for Each Life Stage? Paragraph 2:

Instead of:

“Most notable in terms of predator defense ability is Ko'ko', which was reported to attack and kill small BTS aggressively in Ko'ko' breeding pens. Body and bill size were frequently listed as predator defense traits for Ko'ko', Åga, and sometimes Sihek. Åga was reported to be aggressive toward predators. Respondents noted Åga's intelligence, and its tendency toward alarm calling and mobbing in the presence of a predator. Predatory instincts were also listed for Ko'ko', Åga, and Sihek as a possibly favorable trait for predator defense. Also reported to be aggressive toward predators were Såli and Sihek, and Såli may also use alarm calls to alert neighboring birds of threats. It was suggested that Ko'ko' may outrun BTS. However, we note that BTS is a nocturnal predator, and how these birds may behave at night is not well known. Såli was reported to be skittish on its nest at night and easily flushed, and respondents suggested Åga may also flee a predator at night. However, one respondent shared an observation of Åga remaining calm at night while snakes invaded their nests.”

The correct paragraph should read:

“Most notable in terms of predator defense ability is Ko'ko.' Body and bill size were frequently listed as predator defense traits for Ko'ko', Åga, and sometimes Sihek. Åga was reported to be aggressive toward predators. Respondents noted Åga's intelligence, and its tendency toward alarm calling and mobbing in the presence of a predator. Predatory instincts were also listed for Ko'ko', Åga, and Sihek as a possibly favorable trait for predator defense. Also reported to be aggressive toward predators were Såli and Sihek, and Såli may also use alarm calls to alert neighboring birds of threats. It was suggested that Ko'ko' may outrun BTS. However, we note that BTS is a nocturnal predator, and how these birds may behave at night is not well known. Såli was reported to be skittish on its nest at night and easily flushed, and respondents suggested Åga may also flee a predator at night. However, one respondent shared an observation of Åga remaining calm at night while snakes invaded their nests.”

A correction has been made to Discussion, Paragraph 5:

Instead of:

“Size and aggression were commonly identified as deterrents to BTS predation. As the largest of our focal birds, Ko'ko' was ranked next to least vulnerable in the survey and was reported to behave aggressively toward BTS and to be capable of killing of small snakes (S. Medina 2020, Guam DAWR, oral comm.). Bill and body size were commonly listed for Åga, Ko'ko', and Sihek as traits that may reduce both the probabilities of being encountered and of being killed given an encounter. Although there may have been some confusion among respondents in interpreting our separation of encounter risk from death risk during an encounter, we note the possibility that snakes may adjust their search image after encountering prey that are too large to consume and/or that fiercely counterattack, but this is purely speculative. In terms of habitat preference, Ko'ko' are less likely than other birds to be encountered by BTS, because they nest and forage on the ground (Jenkins, 1979). However, large BTS are less arboreal and are more frequently found in savannas than smaller BTS (Rodda and Reed, 2007; Siers, 2015; Siers et al., 2017b), which may indicate that Ko'ko' would be more likely to be encountered by large BTS that are capable of consuming adult Ko'ko' (Savidge, 1988).”

The correct paragraph should read:

“Size and aggression were commonly identified as deterrents to BTS predation. As the largest of our focal birds, Ko'ko' was ranked next to least vulnerable in the survey. Bill and body size were commonly listed for Åga, Ko'ko', and Sihek as traits that may reduce both the probabilities of being encountered and of being killed given an encounter. Although there may have been some confusion among respondents in interpreting our separation of encounter risk from death risk during an encounter, we note the possibility that snakes may adjust their search image after encountering prey that are too large to consume and/or that fiercely counterattack, but this is purely speculative. In terms of habitat preference, Ko'ko' are less likely than other birds to be encountered by BTS, because they nest and forage on the ground (Jenkins, 1979). However, large BTS are less arboreal and are more frequently found in savannas than smaller BTS (Rodda and Reed, 2007; Siers, 2015; Siers et al., 2017b), which may indicate that Ko'ko' would be more likely to be encountered by large BTS that are capable of consuming adult Ko'ko' (Savidge, 1988).”

The authors apologize for these errors and state that this does not change the scientific conclusions of the article in any way. The original article has been updated.

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References

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