Resistance of Benghal Dayflower (Commelina benghalensis) Seeds to Harsh Environments and the Implications for Dispersal by Mourning Doves (Zenaida macroura) in Georgia, U.S.A

Weed Science ◽  
2009 ◽  
Vol 57 (6) ◽  
pp. 603-612 ◽  
Author(s):  
Russell H. Goddard ◽  
Theodore M. Webster ◽  
Richard Carter ◽  
Timothy L. Grey
Keyword(s):  
Bird Species ◽  
Mechanical Damage ◽  
Harsh Environments ◽  
Gut Contents ◽  
Agricultural Crops ◽  
Zenaida Macroura ◽  
Commelina Benghalensis ◽  
Mourning Doves ◽  
Southern Georgia ◽  
Benghal Dayflower

The potential dispersal of Benghal dayflower seeds by mourning doves was studied in southern Georgia, U.S.A. The gut contents (both crop and gizzard) of mourning doves harvested in the autumn months were investigated to determine if mourning doves fed on Benghal dayflower and whether seeds can survive conditions in the bird gut. Research indicated that mourning doves fed selectively on Benghal dayflower with some harvested birds containing hundreds of Benghal dayflower seeds and capsules in their guts. Further, some seeds recovered remained highly viable. Germination rates in seeds taken from bird crops were similar to controls over the first 4 wk of germination and enhanced over control treatments during the latter 16 wk of a 20-wk germination study. Ultimately, seeds extracted from dove crops had 92% germination as compared to 80% for control seeds. Seeds extracted from dove gizzards had 45% germination, about half that of controls. Benghal dayflower seeds have a structurally reinforced seed coat that probably aids in survival of mechanical damage through bird intestinal tracts. Benghal dayflower seeds exposed to 1.0 M HCl treatment for 2 h had little loss in viability, successfully germinating after such treatment. When evaluating mechanisms for the eradication of Benghal dayflower from agricultural crops, consideration needs to be given to the large number of mourning doves and other bird species that visit cropland and potentially aid in its dispersal.

Inhibiting ventilatory evaporation produces an adaptive increase in cutaneous evaporation in mourning doves Zenaida macroura

1999 ◽  
Vol 202 (21) ◽  
pp. 3021-3028 ◽  
Author(s):  
T.C. Hoffman ◽  
G.E. Walsberg
Keyword(s):  
Skin Surface ◽  
The Body ◽  
Evaporative Heat Loss ◽  
Evaporative Water ◽  
Zenaida Macroura ◽  
Ambient Temperatures ◽  
Rapid Adjustment ◽  
Mourning Doves ◽  
A Minor ◽  
Cutaneous Evaporation

We tested the hypothesis that birds can rapidly change the conductance of water vapor at the skin surface in response to a changing need for evaporative heat loss. Mourning doves (Zenaida macroura) were placed in a two-compartment chamber separating the head from the rest of the body. The rate of cutaneous evaporation was measured in response to dry ventilatory inflow at three ambient temperatures and in response to vapor-saturated ventilatory inflow at two ambient temperatures. At 35 degrees C, cutaneous evaporation increased by 72 % when evaporative water loss from the mouth was prevented, but no increase was observed at 45 degrees C. For both dry and vapor-saturated treatments, cutaneous evaporation increased significantly with increased ambient temperature. Changes in skin temperature made only a minor contribution to any observed increase in cutaneous evaporation. This indicates that Z. macroura can effect rapid adjustment of evaporative conductance at the skin in response to acute change in thermoregulatory demand.

scholarly journals Naturally high plasma glucose levels in mourning doves (Zenaida macroura) do not lead to high levels of reactive oxygen species in the vasculature

Zoology ◽  
2011 ◽  
Vol 114 (3) ◽  
pp. 171-176 ◽  
Author(s):  
Christina L. Smith ◽  
Matthew Toomey ◽  
Benjimen R. Walker ◽  
Eldon J. Braun ◽  
Blair O. Wolf ◽  
...  
Keyword(s):  
Reactive Oxygen Species ◽  
Plasma Glucose ◽  
Reactive Oxygen ◽  
High Plasma ◽  
Oxygen Species ◽  
Zenaida Macroura ◽  
Glucose Levels ◽  
Mourning Doves ◽  
High Plasma Glucose

scholarly journals Using a Commercially Available Enzyme Immunoassay to Quantify Testosterone in Avian Plasma

The Condor ◽  
2007 ◽  
Vol 109 (1) ◽  
pp. 181-186 ◽  
Author(s):  
Brian E. Washburn ◽  
Joshua J. Millspaugh ◽  
Dana L. Morris ◽  
John H. Schulz ◽  
John Faaborg
Keyword(s):  
Enzyme Immunoassay ◽  
Small Volume ◽  
Plasma Testosterone ◽  
Plasma Samples ◽  
Zenaida Macroura ◽  
Vireo Olivaceus ◽  
Testosterone Levels ◽  
Passerina Cyanea ◽  
Assay Procedure ◽  
Mourning Doves

Abstract Abstract Using a commercially available testosterone enzyme immunoassay (EIA), we developed and validated an assay procedure for determining testosterone levels in small-volume (20 µL) avian plasma samples. We evaluated this EIA's utility by measuring plasma testosterone levels in Mourning Doves (Zenaida macroura), White-eyed Vireos (Vireo griseus), Red-eyed Vireos (Vireo olivaceus), and Indigo Buntings (Passerina cyanea). Standard biochemical validations (e.g., parallelism, recovery of exogenous testosterone) demonstrated that the assay accurately and precisely measured testosterone in avian plasma. We compared plasma testosterone levels in males and females of all four species and Indigo Buntings in various reproductive stages to physiologically validate the assay's ability to determine biologically important changes in testosterone levels. Plasma testosterone levels were higher in males compared to females in three of four species. Prebreeding and breeding male Indigo Buntings had higher circulating testosterone levels than postbreeding males. Testosterone levels in our study were similar to reported values for other passerine species using radioimmunoassay procedures. Our results suggest that this EIA procedure is very effective for determining testosterone levels in small-volume avian plasma samples and is sensitive enough to detect biologically important changes in the gonadal activity of birds. Thus, this assay has considerable utility for measuring testosterone in small birds (<15 g), from which only small volumes of plasma (20 µL) can be collected.

scholarly journals First Observations of an Eastern Screech-Owl, Megascops asio, Population in an Apple-Producing Region of Southern Quebec

2006 ◽  
Vol 120 (3) ◽  
pp. 289
Author(s):  
Ngaiou L. Richards ◽  
Pierre Mineau ◽  
David M. Bird ◽  
Pierre Wery ◽  
Jacques Larivée ◽  
...  
Keyword(s):  
Pesticide Exposure ◽  
Zenaida Macroura ◽  
Nest Boxes ◽  
Baseline Information ◽  
Rehabilitation Facilities ◽  
Potential Risks ◽  
Mourning Doves ◽  
Colaptes Auratus ◽  
Using Data ◽  
Not At Risk

Baseline information was collected on a local Eastern Screech-Owl population found in the apple-producing region of Saint-Hilaire and Rougemont, Quebec, as part of a larger study on pesticide exposure conducted between 2000 and 2003. Screech-Owls visited or occupied 41 of 89 nest boxes installed in 12 orchards and 2 control locations. The mean height of occupied nest boxes was 3.83 m (2.00 – 5.80 m). Squirrels, Sciurus and Tamiasciurius sp., and chipmunks, Tamias striatus, Northern Flickers, Colaptes auratus, and wasps were the owls’ primary competitors for the boxes. Intact Screech-Owl pellets retrieved from nest boxes (n = 82) had a mean length and width of 3.57 and 1.44 cm, respectively, and weighed a mean of 1.77 g. Screech-Owls in the study area consumed a variety of small mammal, avian, insect and aquatic prey. Of these, Meadow Voles, Microtus pennsylvanicus, were the predominant prey item identified in pellets, and Mourning Doves, Zenaida macroura, were the primary avian prey found in nest boxes. In Canada, the owl’s trend status remains largely unknown. The species is currently listed as “Not at Risk”, based on an assessment conducted for COSEWIC in 1986. Given that a limited amount of information exists on the natural history and ecology of the species in Quebec, we also generated a map of the owl’s distribution in the province, using data from ornithological databases and rehabilitation facilities. Potential risks to the species within the province, particularly pesticide exposure and habitat loss, are briefly addressed and follow-up studies are discussed.

scholarly journals Using Fecal Glucocorticoids for Stress Assessment in Mourning Doves

The Condor ◽  
2003 ◽  
Vol 105 (4) ◽  
pp. 696-706 ◽  
Author(s):  
Brian E. Washburn ◽  
Joshua J. Millspaugh ◽  
John H. Schulz ◽  
Susan B. Jones ◽  
Tony Mong
Keyword(s):  
Body Mass ◽  
Mourning Dove ◽  
Zenaida Macroura ◽  
Acth Challenge ◽  
Fecal Glucocorticoid Metabolites ◽  
In Captivity ◽  
Mourning Doves ◽  
Para Determinar ◽  
Fecal Glucocorticoids ◽  
Fecal Glucocorticoid

Abstract Fecal glucocorticoid assays provide a potentially useful, noninvasive means to study physiological responses of wildlife to various stressors. The objective of our study was to validate a method for measuring glucocorticoid metabolites in Mourning Dove (Zenaida macroura) feces. We validated the assay using standard procedures (e.g., parallelism, recovery of exogenous corticosterone) to demonstrate that the assay accurately and precisely measured glucocorticoid metabolites in Mourning Dove fecal extracts. We conducted adrenocorticotropin (ACTH) challenge experiments to validate the assay's ability to determine biologically important changes in fecal glucocorticoids. Fecal glucocorticoid levels increased significantly approximately 2–3 hr after administration of ACTH at 50 IU per kg body mass to wild Mourning Doves held in captivity. In contrast, fecal glucocorticoid metabolites did not increase in control birds, birds that received saline injections, or a lower dose of ACTH (1 IU per kg body mass). Variation in overall fecal glucocorticoid metabolite levels may have been influenced by season and the length of time birds were held in captivity. Noninvasive fecal glucocorticoid metabolite analyses, in combination with demographic information, may have considerable utility for monitoring the effects of natural and anthropogenic disturbances on Mourning Dove populations. Uso de Glucocorticoides Fecales Para Evaluar el Estrés en Zenaida macroura Resumen. Las evaluaciones de glucocorticoides fecales representan un medio no invasor potencialmente útil para estudiar las respuestas fisiológicas de los animales silvestres ante agentes causantes de estrés. El objetivo de nuestro estudio fue validar un método para medir metabolitos glucocorticoides en heces de palomas Zenaida macroura. Validamos el método mediante procedimientos estándar (e.g., paralelismo, recuperación de corticosterona exógena) para demostrar que éste mide con exactitud y precisión los metabolitos glucocorticoides en extractos fecales de Z. macroura. Realizamos experimentos de desafío con adrenocorticotropina (ACTH) para validar la habilidad que tenía el método para determinar cambios biológicamente importantes en los glucocorticoides fecales. Los niveles de glucocorticoides fecales aumentaron de forma significativa aproximadamente 2–3 hr después de la administración de ACTH a 50 IU por kg de peso corporal a palomas silvestres mantenidas en cautiverio. En contraste, los metabolitos glucocorticoides fecales no aumentaron en aves control, ni en aves que recibieron inyecciones salinas o una menor dosis de ACTH (1 IU por kg de peso corporal). La variación en los niveles generales de metabolitos glucocorticoides fecales podría haber sido influenciada por la estación y la longitud del período de tiempo en que las aves fueron mantenidas en cautiverio. Los análisis no invasores de metabolitos glucocorticoides, en combinación con información demográfica, podrían ser de considerable utilidad para monitorear los efectos de los disturbios naturales y antropogénicos sobre las poblaciones de Z. macroura.

scholarly journals Environmental Influences on Growth and Reproduction of InvasiveCommelina benghalensis

2016 ◽  
Vol 2016 ◽  
pp. 1-9 ◽  
Author(s):  
Mandeep K. Riar ◽  
Danesha S. Carley ◽  
Chenxi Zhang ◽  
Michelle S. Schroeder-Moreno ◽  
David L. Jordan ◽  
...  
Keyword(s):  
Vegetative Growth ◽  
Soil Nutrition ◽  
Commelina Benghalensis ◽  
Growing Seasons ◽  
Below Ground ◽  
Series Of Experiments ◽  
Noxious Weed ◽  
Highly Weathered Soils ◽  
High Degree ◽  
Benghal Dayflower

Commelina benghalensis(Benghal dayflower) is a noxious weed that is invading agricultural systems in the southeastern United States. We investigated the influences of nutrition, light, and photoperiod on growth and reproductive output ofC. benghalensis. In the first experimental series, plants were grown under high or low soil nutrition combined with either full light or simulated shade. Lowered nutrition strongly inhibited vegetative growth and aboveground spathe production. Similar but smaller effects were exerted by a 50% reduction in light, simulating conditions within a developing canopy. In the second series of experiments,C. benghalensisplants were exposed to different photoperiod conditions that produced short- and long-day plants growing in similar photosynthetic periods. A short-day photoperiod decreased time to flowering by several days and led to a 40 to 60% reduction in vegetative growth, but reproduction above and below ground was unchanged. Collectively, the results indicate that (1) fertility management in highly weathered soils may strongly constrain competitiveness ofC. benghalensis; (2) shorter photoperiods will limit vegetative competitiveness later in the growing seasons of most crops; and (3) the high degree of reproductive plasticity and output possessed byC. benghalensiswill likely cause continual persistence problems in agricultural fields.

Intestinal Helminths in Mourning Doves (Zenaida macroura) from Arizona, Pennsylvania, South Carolina, and Tennessee, U.S.A

10.1654/4091 ◽  
2004 ◽  
Vol 71 (1) ◽  
pp. 81-85 ◽  
Author(s):  
Kelly A. Lee ◽  
J. Christian Franson ◽  
John M. Kinsella ◽  
Tuula HollmÉn ◽  
Scott P. Hansen ◽  
...  
Keyword(s):  
South Carolina ◽  
Intestinal Helminths ◽  
Zenaida Macroura ◽  
Mourning Doves

Diet of mammalian predators in braided river beds in the central South Island, New Zealand

2004 ◽  
Vol 31 (6) ◽  
pp. 631 ◽  
Author(s):  
Elaine C. Murphy ◽  
Rachel J. Keedwell ◽  
Kerry P. Brown ◽  
Ian Westbrooke
Keyword(s):  
New Zealand ◽  
Bird Species ◽  
Gut Contents ◽  
Frequency Of Occurrence ◽  
Braided River ◽  
Braided Rivers ◽  
Rabbit Haemorrhagic Disease ◽  
Mammalian Predators ◽  
Mustela Furo ◽  
Haemorrhagic Disease

In New Zealand, five of the six endemic bird species that breed primarily in South Island braided river beds are classed as threatened. A major cause of decline for these species is predation by introduced mammals, and predator-trapping programs are undertaken in the braided rivers of the Mackenzie Basin to protect them. Trapping programs carried out between September 1997 and April 2001 provided the opportunity to investigate predator diet from the gut contents of 375 cats (Felis catus), 371 ferrets (Mustela furo) and 86 stoats (Mustela erminea). As a percentage frequency of occurrence of the main prey items, cat diet consisted of lagomorphs (present in 70% of guts), birds (in 47%), lizards (30%) and invertebrates (36%). Ferret diet consisted of lagomorphs (69%) and birds (28%). Stoat diet consisted of lagomorphs (50%), birds (51%), lizards (21%) and invertebrates (23%). The frequency of occurrence of birds in all three predators was higher in the spring/summer of 1997 – immediately after rabbit haemorrhagic disease (RHD) was introduced – than in any other previous diet study on these braided rivers. This suggests that RHD did lead to increased predation pressure on birds, at least in the short term.

Cotton Planting Date Affects The Critical Period of Benghal Dayflower (Commelina benghalensis) Control

Weed Science ◽  
2009 ◽  
Vol 57 (1) ◽  
pp. 81-86 ◽  
Author(s):  
Theodore M. Webster ◽  
Timothy L. Grey ◽  
J. Timothy Flanders ◽  
A. Stanley Culpepper
Keyword(s):  
Weed Control ◽  
Critical Period ◽  
Yield Loss ◽  
Maximum Yield ◽  
Growing Season ◽  
Field Studies ◽  
Cotton Field ◽  
Commelina Benghalensis ◽  
Critical Range ◽  
Benghal Dayflower

Benghal dayflower (formerly known as tropical spiderwort) is one of the most troublesome weeds in Georgia cotton. Field studies were conducted from 2003 to 2005 to evaluate the relationship between the duration of Benghal dayflower interference and cotton yield to establish optimum weed-control timing. To determine the critical period of weed control (CPWC), Benghal dayflower interference with cotton was allowed or prohibited in 2-wk intervals between 0 to 12 wk after crop planting. Maximum yield loss from Benghal dayflower in May-planted cotton was 21 to 30% in 2004 and 2005, whereas cotton planting delayed until June resulted in maximum yield losses of 40 to 60%. June-planted cotton had a CPWC of 190 to 800 growing degree days (GDD) in 2004 (52-d interval beginning at 16 d after planting [DAP]) and 190 to 910 GDD in 2005 (59-d interval beginning at 18 DAP). In contrast, May-planted cotton in 2005 had a narrower CPWC interval of 396 to 587 GDD (18 d) that occurred 3 wk later in the growing season (initiated at 39 DAP). May-planted cotton in 2004 did not have a critical range of weed-free conditions. Instead, a single weed removal at 490 GDD (44 DAP) averted a yield loss greater than 5%. It is recommended that fields infested with Benghal dayflower be planted with cotton early in the growing season to minimize weed interference with the crop.

Sign in / Sign up

Export Citation Format

Share Document