Status of Breeding Reddish Egrets on Great Inagua, Bahamas with Comments on Breeding Territoriality and the Effects of Hurricanes

Green, M. Clay; Hill, Austin; Troy, Jeff R.; Holderby, Zachary; Geary, Brock

doi:10.1675/063.034.0210

Cited by 12 publications

(9 citation statements)

References 4 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Furthermore, these results do not offer evidence that reddish egrets possess any particular resilience to coastal disturbances compared to other waterbird species. In fact, due to the specialized aspects of their life history, relying on shallow flats and lagoons to hunt small fish (Lowther & Paul 2002, Holderby et al 2014, reddish egrets may be especially vulnerable to the habitat alterations currently impacting the species' range (Green et al 2011). As coastal development in the Gulf of Mexico increases, due to human populations growing and shifting toward coastal areas (Cendrero & Fischer 1997), habitat is gradually being replaced by man-made structures (Leu et al 2008).…”

Section: Discussionmentioning

confidence: 99%

Movements and survival of juvenile reddish egrets Egretta rufescens on the Gulf of Mexico coast

Geary

Green²,

Ballard³

2015

Endang. Species. Res.

View full text Add to dashboard Cite

Understanding natal dispersal patterns of animals is critical to development of effective species conservation plans, as it ensures that population management takes place at appropriate scales. The reddish egret Egretta rufescens is a threatened waterbird species lacking documentation on many aspects of its ecology, including movement behaviors at all life stages. We attached satellite transmitters to 25 juvenile reddish egrets on their natal colonies and observed their dispersal patterns and subsequent movements over a period of 115 wk (May 2010-August 2012). Birds exhibited the greatest movement rates in the remainder of the first breeding season (through July 2010, ~10 to 13 wk of age, 11.07 km d −1) and steadily decreased in the post-breeding period (4.87 km d −1) and winter (1.96 km d −1) of their first year. Movements of 1 to 2.5 km d −1 characterized the remainder of the tracking period, suggesting that surviving birds were able to establish local territories. Of the 25 tagged birds, 8 (32%) survived throughout the observation period, based on transmitter failure rates, with losses increasing each winter. The majority of birds remained on the Texas/ Mexico coast of the Gulf of Mexico, indicating that the population is largely resident and therefore vulnerable to coastal habitat alterations in the region. Due to a combination of infrequent long-distance migration, specialized behaviors, and apparent limited gene flow, habitat maintenance should be of primary importance for management of this rare species. This is among the first published studies of heron movement ecology using telemetry, and should be followed by further tracking with developing technologies to characterize high-resolution movements and habitat associations.

show abstract

Section: Discussionmentioning

confidence: 99%

Movements and survival of juvenile reddish egrets Egretta rufescens on the Gulf of Mexico coast

Geary

Green²,

Ballard³

2015

Endang. Species. Res.

View full text Add to dashboard Cite

show abstract

“…Currently, about 2,000 breeding pairs are in the United States, and 75 % of the U.S. population resides in Texas (Lowther and Paul 2002;Bates et al 2009). The Bahamas are an important site for Reddish Egrets (Moore and Gape 2008), although surveys there indicate more than a 50 % decline in numbers since the 1980s (Green et al 2011), which is a cause for concern. Because of their limited range, nonmigratory pattern, and colonial nesting, populations can be estimated.…”

Section: Reddish Egretmentioning

confidence: 99%

Avian Resources of the Northern Gulf of Mexico

Burger¹

2017

Habitats and Biota of the Gulf of Mexico: Before the Deepwater Horizon Oil Spill

View full text Add to dashboard Cite

“…The largest concentration of E. r. rufescens is in Texas having an estimated 900-950 breeding pairs: reddish egrets in this region consist of both color morphs (Green 2006). E. r. dickeyi, subspecies found in northwest Mexico, is comprised completely of dark morph individuals while the population in Great Inagua, Bahamas is unique from the others in that it is comprised of primarily (*90%) the white morph (Allen 1955;Scott and Carbonell 1986;Green et al 2011). Blake (1977) suggests that E. r. colorata exhibits slightly paler neck and ornamental plumes and a slightly larger body size though it is more likely that these differences represent seasonal changes rather than geographical variation (Paul 1991).…”

Section: Introductionmentioning

confidence: 99%

“…In Mexico, reddish egrets are officially listed, most recently to 'species of special concern', although very little is known about its population status, population trend, and habitat threats. In the Bahamas, little historical information is available for population estimates of reddish egrets, however recent surveys indicate declining population trends especially on Great Inagua (Scott and Carbonell 1986;Green et al 2011).…”

Section: Introductionmentioning

confidence: 99%

“…Kondrashov and Shpak (1998) suggests that assortative mating may divide a population even in the absence of natural selection. Assortative mating occurs in reddish egrets although the courting of the opposite color morph has been observed (Audubon 1843; Pemberton 1922) and mixed-morph pairing at nests has been reported (Lowther and Paul 2002;Green et al 2011). Each color morph of the reddish egret is attracted differentially to their own plumage coloration during flock formation with all individuals of both morphs landing at like-plumaged decoys (Green and Leberg 2005).…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Genetic diversity and population structure of North America’s rarest heron, the reddish egret (Egretta rufescens)

2011

Self Cite

View full text Add to dashboard Cite

The global distribution of the reddish egret is characterized by disjunct colonies occurring from the Pacific side of Northwest Mexico to the Caribbean. We examined distantly isolated colonies of reddish egret to determine global population genetic structure. We used seven polymorphic microsatellites to accomplish five goals: (1) to assess range wide population differentiation among reddish egret (Egretta rufescens) populations, (2) identify extent of gene flow, (3) determine any historical occurrence of bottlenecks, (4) assess genetic differentiation between color morphs, (5) clarify subspecies status of E. r. dickeyi, a completely dark morph population located in and around the Baja California peninsula, Mexico. Genetic differentiation was dramatic (global Fst = 0.161) throughout the reddish egrets range extending from Baja California, Mexico to Great Inagua, Bahamas. Differentiation occurred among three distinct regions (Fst = 0.238) but not among colonies/ islands within regions suggesting regional philopatry.Genetic diversity (alleles per locus, and heterozygosity) in Baja California Sur, Mexico and Great Inagua, Bahamas populations is lower than in the Texas/Mexico population due to minimal dispersal between regions and smaller population sizes. Dark and white color morphs when present within the same region showed no differentiation. Patterns of recent population bottlenecks are not evident in each of the three regional populations. With evidence of limited gene flow in addition to low genetic diversity and prospects of habitat loss we recommend that reddish egrets be managed as three distinct or evolutionary significant units.

show abstract

Status of Breeding Reddish Egrets on Great Inagua, Bahamas with Comments on Breeding Territoriality and the Effects of Hurricanes

Cited by 12 publications

References 4 publications

Movements and survival of juvenile reddish egrets Egretta rufescens on the Gulf of Mexico coast

Movements and survival of juvenile reddish egrets Egretta rufescens on the Gulf of Mexico coast

Avian Resources of the Northern Gulf of Mexico

Genetic diversity and population structure of North America’s rarest heron, the reddish egret (Egretta rufescens)

Contact Info

Product

Resources

About