Long-term data indicates that supplementary food enhances the number of breeding pairs in a Cape Vulture Gyps coprotheres colony

2016 ◽  
Vol 27 (1) ◽  
pp. 140-152 ◽  
Author(s):  
DANA G. SCHABO ◽  
SONJA HEUNER ◽  
MICHAEL V. NEETHLING ◽  
SASCHA RÖSNER ◽  
ROGER UYS ◽  
...  
Keyword(s):  
Population Dynamics ◽  
Breeding Success ◽  
Food Sources ◽  
Breeding Colony ◽  
Supplementary Food ◽  
Adequate Food ◽  
Vulture Conservation ◽  
Positive Effect ◽  
Term Data

SummaryThe number of vultures is declining in many parts of the world due to numerous threats, such as poisoning and collisions with power-lines as well as the lack of adequate food sources. Vulture restaurants, i.e. supplementary feeding stations, have become a widespread conservation tool aimed at supporting vulture colonies. However, it is poorly understood how vulture restaurants influence population dynamics and whether they affect breeding success of vulture populations. We used a 12-year dataset from a breeding colony of the Cape Vulture Gyps coprotheres and a nearby vulture restaurant in South Africa to investigate the effect of supplementary food on population dynamics and breeding success. We found a significantly positive effect of supplementary food during the nest-building stage on the number of breeding pairs. However, breeding success, i.e. the proportion of successful nests, did not depend on supplementary food during the incubation and rearing stage. Especially during the critical rearing stage, the amount of food supplied might not have been sufficient to meet food demands of the colony. Still, our results indicate that carefully managed vulture restaurants might stabilise vulture colonies and can therefore aid vulture conservation.

scholarly journals Meat sharing between male and female Guinea baboons (Papio papio)

2016 ◽  
Vol 3 (1) ◽  
pp. 1-8 ◽  
Author(s):  
A. S. Goffe ◽  
J. Fischer
Keyword(s):  
Prey Capture ◽  
Food Sources ◽  
Foraging Efficiency ◽  
Multilevel Society ◽  
Status Enhancement ◽  
Papio Papio ◽  
Meat Sharing ◽  
Feeding Tolerance ◽  
Term Data

Abstract. Meat sharing in non-human primates has been linked to a variety of functions, including harassment reduction, mate provisioning and status enhancement. We present observational data regarding male prey capture and male–female meat sharing in wild Guinea baboons. Guinea baboons live in a multilevel society that comprises units of males with associated females and, sometimes, secondary males. Several males of different units maintain strong bonds, resulting in the formation of parties within gangs. Female–male relationships persist irrespective of female reproductive states, yet females may also switch between males at all stages of the reproductive cycle. Our data show that males capture and kill a variety of prey, including hares and antelope. Males shared meat passively only with females in their social and reproductive units. The occurrence of oestrus females in the gang did not influence whether or not sharing would occur in that males did not share with oestrus females unless an affiliative relationship already persisted, indicating that short-term currency exchanges of meat for sex are unlikely. We hypothesise that males may benefit from feeding tolerance by retaining females, while females may increase access to potentially nutritious and rare food sources. Alternatively, females may prefer males that are generally less aggressive and thus also more likely to share meat. Long-term data will be needed to ultimately distinguish between the two accounts. Although there is no evidence that males intentionally provide necessary resources to particular females during times of high energetic demands and decreased foraging efficiency, as has been found in humans, and meat sharing is generally rare, it may have subtle, yet important effects on the maintenance of bonds in Guinea baboons.

Author response for "Apparent breeding success drives long‐term population dynamics of a migratory swan"

2020 ◽  
Author(s):  
Rascha J.M. Nuijten ◽  
Stefan J.G. Vriend ◽  
Kevin A. Wood ◽  
Trinus Haitjema ◽  
Eileen C. Rees ◽  
...  
Keyword(s):  
Population Dynamics ◽  
Breeding Success ◽  
Author Response

scholarly journals Apparent breeding success drives long‐term population dynamics of a migratory swan

2020 ◽  
Vol 51 (11) ◽  
Author(s):  
Rascha J. M. Nuijten ◽  
Stefan J. G. Vriend ◽  
Kevin A. Wood ◽  
Trinus Haitjema ◽  
Eileen C. Rees ◽  
...  
Keyword(s):  
Population Dynamics ◽  
Breeding Success

scholarly journals Female sociality and sexual conflict shape offspring survival in a Neotropical primate

2017 ◽  
Vol 114 (8) ◽  
pp. 1892-1897 ◽  
Author(s):  
Urs Kalbitzer ◽  
Mackenzie L. Bergstrom ◽  
Sarah D. Carnegie ◽  
Eva C. Wikberg ◽  
Shoji Kawamura ◽  
...  
Keyword(s):  
Social Relationships ◽  
Offspring Survival ◽  
Infant Survival ◽  
Bond Stability ◽  
Fitness Consequences ◽  
Rank Difference ◽  
Kin Relationship ◽  
Positive Effect ◽  
Term Data

Most mammals live in social groups in which members form differentiated social relationships. Individuals may vary in their degree of sociality, and this variation can be associated with differential fitness. In some species, for example, female sociality has a positive effect on infant survival. However, investigations of such cases are still rare, and no previous study has considered how male infanticide might constrain effects of female sociality on infant survival. Infanticide is part of the male reproductive strategy in many mammals, and it has the potential to override, or even reverse, effects of female reproductive strategies, including sociality. Therefore, we investigated the relationships between female sociality, offspring survival, and infanticide risk in wild white-faced capuchin monkeys using long-term data from Santa Rosa, Costa Rica. Female capuchins formed differentiated bonds, and bond strength was predicted by kin relationship, rank difference, and the presence of female infants. Most females formed stable bonds with their top social partners, although bond stability varied considerably. Offspring of highly social females, who were often high-ranking females, exhibited higher survivorship during stable periods compared with offspring of less social females. However, offspring of highly social females were more likely to die or disappear during periods of alpha male replacements, probably because new alpha males are central to the group, and therefore more likely to target the infants of highly social, central females. This study shows that female sociality in mammals can have negative fitness consequences that are imposed by male behavior.

Crop rotations with clover and their productivity

2020 ◽  
Author(s):  
Ol'ga Gladysheva ◽  
Oksana Artyuhova ◽  
Vera Svirina
Keyword(s):  
Forest Soil ◽  
Crop Rotation ◽  
Gray Forest Soil ◽  
Arable Land ◽  
Perennial Grasses ◽  
Crop Rotations ◽  
Field Crop ◽  
Pure Steam ◽  
Positive Effect

The results of long-term research in experiments with crop rotations with different clover saturation are presented. It is shown that the cluster has a positive effect on the main indicators of vegetation of dark-gray forest soil. The introduction of two fields of perennial grasses into the six-field crop rotation significantly increases both the humus reserves and increases the productivity of arable land by 1.5–2 times compared to the crop rotation with a field of pure steam.

The depressing (negative) effect of oestradiol benzoate on the in vitro secretion of LH and FSH by the pituitary gland of the LRH-pretreated long-term ovariectomized rat changes into the augmentative (positive) effect after discontinuation of the LRH-pretreatment

1985 ◽  
Vol 110 (3) ◽  
pp. 329-337 ◽  
Author(s):  
G. A. Schuiling ◽  
H. Moes ◽  
T. R. Koiter
Keyword(s):  
Depressing Effect ◽  
Ovx Rats ◽  
Gonadotrophin Secretion ◽  
Oestradiol Benzoate ◽  
Negative Effect ◽  
Positive Effect ◽  
Perifusion System

Abstract. The effect of pretreatment in vivo with oestradiol benzoate on in vitro secretion of LH and FSH was studied in long-term ovariectomized (OVX) rats both at the end of a 5-day continuous in vivo pretreatment with LRH and 4-days after cessation of such LRH pretreatment. Rats were on day 0 sc implanted with osmotic minipumps which released LRH at the rate of 250 ng/h. Control rats were implanted with a piece of silicone elastomer with the dimensions of a minipump. On days 2 and 4 the rats were injected with either 3 μg EB or with oil. On day 5 part of the rats were decapitated and the in vitro autonomous (i.e. non-LRH-stimulated) and 'supra-maximally' LRHstimulated release of LH and FSH was studied using a perifusion system. From other rats the minipumps were removed on day 5 and perifusion was performed on day 9. On the 5th day of the in vivo LRH pretreatment the pituitary LH/FSH stores were partially depleted; the pituitaries of the EB-treated rats more so than those of the oil-injected rats. EB alone had no significant effect on the content of the pituitary LH- and FSH stores. On day 9, i.e. 4 days after removal of the minipumps, the pituitary LH and FSH contents had increased in both the oil- and the EB injected rats, but had not yet recovered to control values. In rats not subjected to the 5-days pretreatment with LRH EB had a positive effect on the supra-maximally LRH-stimulated secretion of LH and FSH as well as on the non-stimulated secretion of LH. EB had no effect on the non-stimulated secretion of FSH. After 5 days of in vivo pretreatment with LRH only, the in vitro non-stimulated and supra-maximally LRH-stimulated secretion of both LH and FSH were strongly impaired, the effect correlating well with the LRH-induced depletion of the pituitary LH/FSH stores. In such LRH-pretreated rats EB had on day 5 a negative effect on the (already depressed) LRH-stimulated secretion of LH (not on that of FSH). EB had no effect on the non-stimulated LH/FSH secretion. It could be demonstrated that the negative effect of the combined LRH/EB pretreatment was mainly due to the depressing effect of this treatment on the pituitary LH and FSH stores: the effect of oestradiol on the pituitary LRH-responsiveness (release as related to pituitary gonadotrophin content) remained positive. In LRH-pretreated rats, however, this positive effect of EB was smaller than in rats not pretreated with LRH. Four days after removal of the minipumps there was again a positive effect of EB on the LRH-stimulated secretion of LH and FSH as well as on the non-stimulated secretion of LH. The positive effect of EB on the pituitary LRH-responsiveness was as strong as in rats which had not been exposed to exogenous LRH. The non-stimulated secretion of FSH was again not affected by EB. The results demonstrate that the effect of EB on the oestrogen-sensitive components of gonadotrophin secretion consists of two components: an effect on the pituitary LRH-responsiveness proper, and an effect on the pituitary LH/FSH stores. The magnitude of the effect of EB on the LRH-responsiveness is LRH dependent: it is very weak (almost zero) in LRH-pretreated rats, but strong in rats not exposed to LRH as well as in rats of which the LRH-pretreatment was stopped 4 days previously. Similarly, the effect of EB on the pituitary LH and FSH stores is LRH-dependent: in the absence of LRH, EB has no influence on the contents of these stores, but EB can potentiate the depleting effect of LRH on the LH/FSH-stores. Also this effect disappear after cessation of the LRH-pretreatment.

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