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(1 - 9 of 9)
- Title
- A comparison of reproductive success in early and late breeding Sooty Terns (Sterna fuscata) in the dry tortugas.
- Creator
- Plantier, Terry Lynn., Florida Atlantic University, Mahoney, Sheila A.
- Abstract/Description
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Evidence indicates that earlier-nesting birds are often older, choose preferred nest sites, and have greater reproductive success than those nesting later. The Sooty Terns at Bush Key appear to follow a similar pattern. The first birds arrive at the west end of the breeding grounds three weeks earlier than birds at the east end and behaviorally appear to be older and more experienced. The west birds settle in the more desirable habitats (the west end was cooler than the east end) and laid...
Show moreEvidence indicates that earlier-nesting birds are often older, choose preferred nest sites, and have greater reproductive success than those nesting later. The Sooty Terns at Bush Key appear to follow a similar pattern. The first birds arrive at the west end of the breeding grounds three weeks earlier than birds at the east end and behaviorally appear to be older and more experienced. The west birds settle in the more desirable habitats (the west end was cooler than the east end) and laid larger eggs, hatched larger chicks, enjoyed greater hatchability, fed their chicks at a lower frequency when they were young, and had greater reproductive success than birds in the east. This was accomplished through a combination of choosing physically and thermally more favorable habitat, which was more centrally located, being more persistent incubators and brooders, and, by nesting earlier, having larger, less-easily eaten chicks by the time avian predators arrived on the island.
Show less - Date Issued
- 1988
- PURL
- http://purl.flvc.org/fcla/dt/14446
- Subject Headings
- Sooty tern, Sea birds--Florida--Dry Tortugas--Reproduction
- Format
- Document (PDF)
- Title
- Population trends and breeding ecology of the Florida burrowing owl (Athene cunicularia floridana) on the Florida Atlantic University campus, 1990--2003.
- Creator
- McKie, Annabelle C., Florida Atlantic University, Mahoney, Sheila A.
- Abstract/Description
-
From 1990 to 2003 a study of the declining population of Burrowing Owls (Athene cunicularia floridana) on the Florida Atlantic University campus in Palm Beach County indicated that the location of unsuccessful owl (those not producing chicks) territories was the cause of their decline. Over the 14 years, the number of successful adult owls and the number of chicks remained fairly constant because they were located in areas where campus expansion remained minimal. Also, 76% of owls that reused...
Show moreFrom 1990 to 2003 a study of the declining population of Burrowing Owls (Athene cunicularia floridana) on the Florida Atlantic University campus in Palm Beach County indicated that the location of unsuccessful owl (those not producing chicks) territories was the cause of their decline. Over the 14 years, the number of successful adult owls and the number of chicks remained fairly constant because they were located in areas where campus expansion remained minimal. Also, 76% of owls that reused territories were reproductively successful, whereas only 43% of owls on newly-established territories were successful. Additionally, territories occupied for seven years or more averaged 1.27 chicks per territory per year, while territories occupied less than seven years averaged 0.17 chicks. Furthermore, all of the territories occupied for seven years or more produced chicks, but only 58% of territories occupied less than seven years did so. Territories located in Pomello sand produced more chicks, as burrows there never flooded and also were less exposed to construction. Chicks from territories with one burrow dispersed faster (75 days of age) than did those from territories with two or more burrows (119 days of age).
Show less - Date Issued
- 2003
- PURL
- http://purl.flvc.org/fcla/dt/13093
- Subject Headings
- Athene (Birds)--Florida, Burrowing owl--Ecology, Burrowing owl--Breeding
- Format
- Document (PDF)
- Title
- Relationships of caecal lengths to food habits in North American and other birds.
- Creator
- Poppema, Teresa Faye., Florida Atlantic University, Mahoney, Sheila A.
- Abstract/Description
-
This study elucidates patterns of occurrence and the role of caeca in 166 species of birds having a diversity of food habits. Well-developed caeca occur in granivorous, herbivorous, insectivorous, and some carnivorous (those consuming aquatic invertebrates and some small vertebrates) species whose diets contain large amounts of cellulose or chitin. Poorly-developed or none-existent caeca occur in frugivorous, nectarivorous, piscivorous, and other carnivorous (those consuming carrion, some...
Show moreThis study elucidates patterns of occurrence and the role of caeca in 166 species of birds having a diversity of food habits. Well-developed caeca occur in granivorous, herbivorous, insectivorous, and some carnivorous (those consuming aquatic invertebrates and some small vertebrates) species whose diets contain large amounts of cellulose or chitin. Poorly-developed or none-existent caeca occur in frugivorous, nectarivorous, piscivorous, and other carnivorous (those consuming carrion, some small vertebrates) species whose diets consist mainly of soluble sugars and proteins. There were no significant age or sex differences in caecal lengths of selected species and caecal lengths are not correlated with body mass. Caecal length does, however, correlate well with small intestine length in species that ferment cellulose and possibly chitin, and with large intestine length in species that are potentially waterstressed and/or consume a low protein diet. Caeca function in digestion of insoluble food and may help conserve critical resources such as water and nitrogen.
Show less - Date Issued
- 1990
- PURL
- http://purl.flvc.org/fcla/dt/14582
- Subject Headings
- Cecum, Digestive organs--Birds, Birds--Food
- Format
- Document (PDF)
- Title
- Reproductive success and nestling growth at a roof and ground colony of roseate terns (Sterna dougallii) in Florida.
- Creator
- Zambrano, Ricardo, Florida Atlantic University, Mahoney, Sheila A.
- Abstract/Description
-
Few studies have addressed reproductive success and nestling growth of the Caribbean population of Roseate Terns (Sterna dougallii), and no one has studied the most northerly nesting colonies in Florida. Two colonies in Florida, a ground colony (Pelican Shoal), and a roof colony (Marathon Government Center) were examined in 2000 and 2001. This study found the roof and ground colony to have similar incubation periods, days to fledging, linear growth rates, and asymptotic mass. However, clutch...
Show moreFew studies have addressed reproductive success and nestling growth of the Caribbean population of Roseate Terns (Sterna dougallii), and no one has studied the most northerly nesting colonies in Florida. Two colonies in Florida, a ground colony (Pelican Shoal), and a roof colony (Marathon Government Center) were examined in 2000 and 2001. This study found the roof and ground colony to have similar incubation periods, days to fledging, linear growth rates, and asymptotic mass. However, clutch size, hatch success, and annual reproductive success were more variable between the colonies and between the two years. Most of this variability resulted from high nest and chick loss at Pelican Shoal due to avian predators, nesting sea turtles, and strong summer storms. Artificial habitat (nest boxes and tires), placed at the two colonies to improve reproductive success, was not utilized by Roseate Terns for nesting but was used by nesting Bridled Terns (Sterna anaethetus ) at Pelican Shoal. Air temperatures were higher at the roof colony than the ground colony and higher in the artificial habitat than in "natural" nesting substrates.
Show less - Date Issued
- 2001
- PURL
- http://purl.flvc.org/fcla/dt/12866
- Subject Headings
- Roseate tern--Florida, Birds--Infancy, Birds--Reproduction
- Format
- Document (PDF)
- Title
- Reproductive success, territory size, and predation pressures of the Florida scrub-jay (Aphelocoma coerulescens) at Savannas Preserve State Park.
- Creator
- Cowan, Ernest M., Florida Atlantic University, Mahoney, Sheila A.
- Abstract/Description
-
The Florida Scrub-jay is found only in the fire-dependent xeric oak communities of Florida. The number of scrub-jays statewide has been in steady decline over the past century due to the habitat loss resulting from urban development and the aging of xeric oak scrub caused by fire suppression policies. This study looks how aging of the scrub has affected scrub-jays at the Savannas Preserve State Park in Port St. Lucie, Florida. The population of scrub-jays at Savannas has been in decline over...
Show moreThe Florida Scrub-jay is found only in the fire-dependent xeric oak communities of Florida. The number of scrub-jays statewide has been in steady decline over the past century due to the habitat loss resulting from urban development and the aging of xeric oak scrub caused by fire suppression policies. This study looks how aging of the scrub has affected scrub-jays at the Savannas Preserve State Park in Port St. Lucie, Florida. The population of scrub-jays at Savannas has been in decline over the past eight years. This study revealed that they are occupying territories that are much smaller than the normal optimal size and are having minimal reproductive success. In addition, the birds are subjected to predation pressures from natural predators present at higher than normal densities and by other predators brought into their habitat by encroaching urban development. The implementation of an aggressive prescribed fire program to restore their habitat is crucial to the long-term survival of this population of Florida Scrub-jays.
Show less - Date Issued
- 2005
- PURL
- http://purl.flvc.org/fcla/dt/13204
- Subject Headings
- Florida scrub jay--Geographical distribution, Florida scrub jay--Reproduction, Bird populations--Florida, Birds--Effect of habitat modification on--Florida, Wildlife conservation--Florida
- Format
- Document (PDF)
- Title
- Hatching, fledging success and thermoregulatory behaviors of roof-nesting least terns (Sterna antillarum).
- Creator
- Cimbaro, John Stephen., Florida Atlantic University, Mahoney, Sheila A.
- Abstract/Description
-
Least Terns (Sterna antillarum) have recently shifted from traditional beach nesting sites to flat gravel roofs in parts of their range. In an attempt to determine whether the thermal environment of novel roof sites contributes to nesting success relative to that of traditional sites, hatching and fledging success and fifteen possible thermoregulatory behaviors of roof-nesting Least Terns were examined at four sites in Palm Beach County, Florida in 1992. The mean numbers of chicks and...
Show moreLeast Terns (Sterna antillarum) have recently shifted from traditional beach nesting sites to flat gravel roofs in parts of their range. In an attempt to determine whether the thermal environment of novel roof sites contributes to nesting success relative to that of traditional sites, hatching and fledging success and fifteen possible thermoregulatory behaviors of roof-nesting Least Terns were examined at four sites in Palm Beach County, Florida in 1992. The mean numbers of chicks and fledglings produced/nest (1.13 and 0.70, respectively) were significantly higher than those reported in other recent studies, indicating that nesting on some roofs is successful and may be a good alternative to beach locations. There was no difference between equivalent temperatures at the roofs and at a nearby beach, thereby suggesting that the new thermal environments of roofs do not adversely influence hatching and fledging success in Least Terns.
Show less - Date Issued
- 1993
- PURL
- http://purl.flvc.org/fcla/dt/14900
- Subject Headings
- Sternula antillarum--Breeding, Birds--Infancy, Nest building
- Format
- Document (PDF)
- Title
- Growth of the brown noddy (Anous stolidus) in the Dry Tortugas.
- Creator
- Wolfe, Cynthia Ann, Florida Atlantic University, Mahoney, Sheila A.
- Abstract/Description
-
Brown Noddy nestlings in the Dry Tortugas exhibit a growth rate that is slower than would be predicted, based on adult body size and mode of development. This pattern of prolonged growth is typical of tropical pelagic seabirds. An intraspecific comparison of growth rates among several populations of Brown Noddies indicates that growth of body mass of the Tortugas Noddies is significantly faster, the development period shorter, and the asymptotic size smaller than in Pacific populations....
Show moreBrown Noddy nestlings in the Dry Tortugas exhibit a growth rate that is slower than would be predicted, based on adult body size and mode of development. This pattern of prolonged growth is typical of tropical pelagic seabirds. An intraspecific comparison of growth rates among several populations of Brown Noddies indicates that growth of body mass of the Tortugas Noddies is significantly faster, the development period shorter, and the asymptotic size smaller than in Pacific populations. However, there were no differences among the populations in the rates of wing or culmen growth. The Bush Key nestlings appear to receive a higher quality diet that contains proportionally more fish, while the Pacific nestlings receive substantial amounts of squid. The Pacific nestlings also seem to be subjected to a thermally more stressful microclimate, which may necessitate the allocation of proportionally more of their total energy to thermoregulation and less to growth.
Show less - Date Issued
- 1989
- PURL
- http://purl.flvc.org/fcla/dt/14502
- Subject Headings
- Terns, Sea birds--Florida--Dry Tortugas
- Format
- Document (PDF)
- Title
- The use of nesting initiation dates of roseate spoonbills ( Ajaia ajaja) in northeastern Florida Bay as an ecosystem indicator for water management practices, 1935--1999.
- Creator
- Alvear Rodriguez, Elsa Marcella., Florida Atlantic University, Ogden, John C., Mahoney, Sheila A.
- Abstract/Description
-
Quantity and timing of freshwater flow from the Everglades to Florida Bay varied under different water management practices in the twentieth century, with negative ecological repercussions. Ecological indicators that respond to differences in hydrology, such as wading bird colony dynamics, can be used for hydrological restoration projects. I examined the possibility of using timing of nesting of Roseate Spoonbills (Ajaia ajaja) in northeastern Florida Bay as an ecological indicator. Nest...
Show moreQuantity and timing of freshwater flow from the Everglades to Florida Bay varied under different water management practices in the twentieth century, with negative ecological repercussions. Ecological indicators that respond to differences in hydrology, such as wading bird colony dynamics, can be used for hydrological restoration projects. I examined the possibility of using timing of nesting of Roseate Spoonbills (Ajaia ajaja) in northeastern Florida Bay as an ecological indicator. Nest initiation dates (N = 51) from 1936--1999 (x = November 25) were calculated from numerous published and unpublished sources. The dates were strikingly consistent and did not show significant trends over the entire study period, nor did the dates differ among periods of different water management practices. Early dates were not correlated with favorable hydrologic conditions (low water levels, fast drying rates) in spoonbill foraging habitat. Spoonbill timing of nesting appears to be a poor ecological indicator for Florida Bay.
Show less - Date Issued
- 2001
- PURL
- http://purl.flvc.org/fcla/dt/12763
- Subject Headings
- Roseate spoonbill--Nests, Indicators (Biology)--Florida--Florida Bay, Water quality biological assessment--Florida--Florida Bay
- Format
- Document (PDF)
- Title
- The effect of medroxyprogesterone (Depo-Provera) on the ovaries of captive cockatiels (Nymphicus holiandicus) during the reproductive cycle.
- Creator
- Juillerat, Dana Kale, Florida Atlantic University, Mahoney, Sheila A., Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
-
Depo-Provera, a drug manufactured by the Upjohn Company, has been used clinically to prevent egg-laying in several species of domestic birds. Two different doses of the drug plus a placebo injection of saline were administered to 54 cockatiels. All subjects appeared normal and healthy throughout the study except for two birds in the higher dose treatment which died of unknown causes. Control was studied through the direct observation of the ovary by means of laparoscopy, as well as monitoring...
Show moreDepo-Provera, a drug manufactured by the Upjohn Company, has been used clinically to prevent egg-laying in several species of domestic birds. Two different doses of the drug plus a placebo injection of saline were administered to 54 cockatiels. All subjects appeared normal and healthy throughout the study except for two birds in the higher dose treatment which died of unknown causes. Control was studied through the direct observation of the ovary by means of laparoscopy, as well as monitoring egg laying activity throughout the study. Depo-Provera at both doses tested appears to effectively decrease egg-laying activity in the captive cockatiel. All birds receiving the higher dose of Depo-Provera gained significant weight. Although the use of Depo-Provera may serve as a means of preventive medicine, there are serious side effects that should be considered.
Show less - Date Issued
- 1997
- PURL
- http://purl.flvc.org/fcla/dt/15466
- Subject Headings
- Medroxyprogesterone, Cockatiel, Birds--Reproduction
- Format
- Document (PDF)
