THE GENETICS OF THE COLOUR PHASES OF THE RED FOX IN THE MACKENZIE RIVER LOCALITY

1947 ◽  
Vol 25d (6) ◽  
pp. 190-215 ◽  
Author(s):  
L. Butler
Keyword(s):  
Red Fox ◽  
Low Frequency ◽  
Coat Colour ◽  
Population Trend ◽  
Population Increase ◽  
Population Cycle ◽  
Gene Frequencies ◽  
Eastern Canada ◽  
Migrant Populations ◽  
In The Wild

The red fox (Vulpes fulva) exists in the wild in three coat colour phases; red, cross, and silver or black. These three phases result from the action of one pair of alleles, the homozygotes being silver and red and the heterozygote being cross. At least two different mutations have occurred giving rise to the Canadian gene in eastern Canada and the Alaskan gene in western Canada. The mixing of these two mutant genes complicates the gene frequency analysis.The proportions of the three colour phases are shown to vary with (1) locality, (2) state of population cycle, (3) population trend, (4) migration pressure. Of these factors the variations with locality and population trend are fairly satisfactorily explained by selection but the fluctuation of colour phase proportions with the population cycle is not. On the other hand all the facts can be explained by a migration theory, with or without selection. By migration, a mixture of native and migrant populations with different gene frequencies is obtained. Such migrations tend to be rhythmic since they are connected with the population cycle. In the year that migration took place the pelt returns reveal aberrant gene frequencies or colour phase ratios. In the following years the gene frequencies quickly approach equilibrium that may be at the premigration level or at a new one depending upon the success of the migrants in establishing themselves in the breeding population.The marked diminution in the percentage silver and cross is due to the rapid population increase in an area of low frequency of the silver producing gene and the migration of this type into areas of higher frequency.

Assisted colonisation trial of the eastern barred bandicoot (Perameles gunnii) to a fox-free island

2017 ◽  
Vol 44 (7) ◽  
pp. 484 ◽  
Author(s):  
Rebecca Groenewegen ◽  
Dan Harley ◽  
Richard Hill ◽  
Graeme Coulson
Keyword(s):  
Habitat Use ◽  
Body Condition ◽  
Red Fox ◽  
Suitable Habitat ◽  
Viable Option ◽  
Predator Exclusion ◽  
In The Wild ◽  
Radio Transmitters ◽  
Release Group ◽  
Small Sites

Context Assisted colonisation has the potential to protect species from intractable threats within their historical ranges. The Australian mainland subspecies of the eastern barred bandicoot (Perameles gunnii) is extinct in the wild, with surviving populations restricted to small sites protected by predator–barrier fences. PVA modelling shows that a self-sustaining bandicoot population would require an area free of the introduced red fox (Vulpes vulpes) of at least 2500ha. French Island is outside the historic range of the species, but is fox-free and contains around 9000ha of potentially suitable habitat. Aims This study will assess the suitability of French Island as a potential site for a self-sustaining eastern barred bandicoot population by conducting a 1-year assisted colonisation trial to assess habitat use, body condition and survival. Methods Between July and September 2012, 18 adult bandicoots were released. We radio-tracked bandicoots using intraperitoneal radio-transmitters for up to 122 days and trapped fortnightly. Key results The release group met the three measures of success: (1) appropriate habitat use; (2) recovery of post-release bodyweight; and (3) founder survival exceeding 100 days. Habitat use and body condition throughout the trial reflected that of mainland populations, and seven bandicoots survived longer than 100 days. Mortality was greatest in the first month, with veterinary investigations confirming two deaths due to cat predation, two deaths from toxoplasmosis and one unknown cause of death. Bandicoots that survived longer than 100 days occupied higher, drier ground than those that did not. Toxoplasmosis cases were associated with lower topographic position on the site. Conclusions Our results suggest that French Island provides suitable habitat for the establishment of a population of eastern barred bandicoots. On French Island, toxoplasmosis was identified as an important source of mortality in addition to cat predation, and warrants further investigation. Implications Given the costs and challenges of predator control and the maintenance of predator exclusion fences, assisted colonisation to one or more fox-free islands remains the most viable option to establish self-sustaining bandicoot populations. Our results highlight the value in conducting trial releases ahead of major translocations.

scholarly journals Red hind Epinephelus guttatus Vocal Repertoire Characterization, Behavior and Temporal Patterns

2020 ◽  
Vol 31 ◽  
pp. GCFI31-GCFI41
Author(s):  
Carlos M. Zayas Santiago ◽  
Richard S. Appeldoorn ◽  
Michelle T. Schärerer-Umpierre ◽  
Juan J. Cruz-Motta
Keyword(s):  
Low Frequency ◽  
Temporal Patterns ◽  
Spawning Aggregations ◽  
Red Hind ◽  
In Captivity ◽  
In The Wild ◽  
Epinephelus Guttatus ◽  
Spatio Temporal ◽  
Passive Acoustic ◽  
Female Call

Passive acoustic monitoring provides a method for studying grouper courtship associated sounds (CAS). For Red Hind (Epinephelus guttatus), this approach has documented spatio—temporal patterns in their spawning aggregations. This study described vocalizations produced by E. guttatus and their respective behavioral contexts in field and laboratory studies. Five sound types were identified, which included 4 calls recorded in captivity and one sound recorded in the wild, labeled as Chorus. Additionally, the Grunt call type recorded was presumed to be produced by a female. Call types consisted of variations and combinations of low frequency (50—450 Hz) pulses, grunts and tonal sounds in different combinations. Common call types exhibited diel and lunar oscillations during the spawning season, with both field and captive recordings peaking daily at 1800 AST and at 8 days after the full moon.

Effects of behaviour selection on litter size, fetal development and plasma progesterone concentrations during pregnancy in silver fox vixens

2002 ◽  
Vol 2002 ◽  
pp. 125-125
Author(s):  
L. V. Osadchuk
Keyword(s):  
Reproductive Function ◽  
Coat Colour ◽  
Performance Potential ◽  
Plasma Progesterone ◽  
Term Selection ◽  
Silver Fox ◽  
In The Wild ◽  
Selection For ◽  
And Control

Animal domestication is a natural selection experiment the important result of which is a great increase in the rate of appearance of new forms and in the wild range of variation of organisms. Analysing different aspects of this problem, D.K. Belyaev has came to a hypothesis that the morphological and physiological reorganisation of domestic animals has been going by the way of unconscious selection of animals on their behaviour, carried out by person at the very first stages of domestication (Belyaev, 1979). To testify this hypothesis, a population of tame silver foxes has been produced in long-term selection for lack of aggression and fear towards humans (domestic behaviour) at the Institute of Cytology and Genetics in Novosibirsk, Russia. In the process of selection the genetic transformation of behaviour and morphology, and physiological functions has been observed (Trut, 1999). In particular, selected animals show no aggressiveness to man, behave amicably towards humans and have some changes in the coat colour and body constitution (Trut, 1999). The important part of Belyaev’s hypothesis was the assumption that selection for domestic behaviour could affect the reproductive function, in particular the pituitary-gonadal axis controlling reproduction and fertility. The aim of this study was to obtain information about possible changes in reproduction between control (C) and domesticated (D) vixens. Reproductive performance, potential fertility, embryonic mortality and fetal viability were analysed for vixens from domesticated and control population. In addition, plasma progesterone concentrations were determined in selected and control females during pregnancy.

Genetic and demographic effects of single wild-type immigrants on a mutant population of Tribolium castaneum

1986 ◽  
Vol 28 (6) ◽  
pp. 1003-1008 ◽  
Author(s):  
Michael A. Delgado ◽  
DuWayne C. Englert
Keyword(s):  
Tribolium Castaneum ◽  
Wild Type ◽  
Gene Frequencies ◽  
Treatment Groups ◽  
Female Immigrant ◽  
Rate Of Increase ◽  
Wild Type Male ◽  
Wild Type Female ◽  
In The Wild ◽  
Type Gene

The effects of single wild-type immigrants on populations of Tribolium castaneum initially homozygous for the antennapedia (ap) allele were examined in reference to gene frequencies and age structures. One population received a wild-type male, another received a wild-type female, and the control population received no wild-type immigrant. The rate of increase in the wild-type gene frequency was significantly higher in the female immigrant population. Rapid increase in heterozygosity for this population resulted in a higher average number of adults than for the other two treatment groups. No significant differences in the numbers of larvae and pupae were observed. Results indicated increased larval survivability to be the major factor in establishment of the wild-type gene and the sex of the immigrant in the rate of increase.Key words: Tribolium, population, selection, immigration, antennapedia.

Blood Protein Polymorphism in Harp Seals off Eastern Canada

1969 ◽  
Vol 26 (5) ◽  
pp. 1397-1399 ◽  
Author(s):  
Gunnar Nævdal
Keyword(s):  
East Coast ◽  
Protein Polymorphism ◽  
Blood Protein ◽  
Gene Frequencies ◽  
Eastern Canada ◽  
Blood Samples ◽  
Frequency Distributions ◽  
Significant Difference ◽  
Zone Electrophoresis

Blood samples from 208 harp seals taken in the Gulf of St. Lawrence and 175 taken off the east coast of Newfoundland showed no significant difference in frequency distributions of the serum transferrins or in gene frequencies. The samples were collected in the pupping season and analyzed by zone electrophoresis.

scholarly journals Gene Frequencies in the Domestic Cats of Adelaide

1973 ◽  
Vol 26 (5) ◽  
pp. 1215 ◽  
Author(s):  
JM Clark
Keyword(s):  
Sex Ratio ◽  
Urban Areas ◽  
Human Population ◽  
Coat Colour ◽  
Domestic Cats ◽  
Gene Frequencies ◽  
Stray Cats

A survey of 600 stray cats from industrial-urban areas of Adelaide was conducted and the frequencies of some genes controlling coat colour were determined. The sample fitted a I : 1 sex ratio and comparison of observed and expected phenotypes at the orange locus established that the population was panmictic. The frequencies for d (0�326) and S (0�295) were significantly different from those in another area in Australia. A possible reason for this difference, based on different human population origins and preferences, is proposed. The frequencies of /, a, W, tb , and 0 did not differ greatly from those in other areas in Australia.

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