Table 2 - uploaded by Mduduzi Ndlovu
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Source publication
The daily movements of 18 Egyptian Geese (Alopochen aegyptiaca) in South Africa were recorded using satellite telemetry. General additive mixed models were used to explain the distances moved by the birds at different times of the day, correcting for sex, site, season and individual. Distances moved by birds in the mesic, winter-rainfall, south-wes...
Contexts in source publication
Context 1
... a daily basis, most movements by non-moulting Egyptian Geese (n = 4321) were between 1 and 10 km daily (Table 2). There were 85 instances of birds tagged at Barberspan moving >100 km in a day and 21 of these were in the first month after moult was completed (Month 1) and 16 in Month 11 after moult. ...
Context 2
... flights were predominantly undertaken at night (88%) and were associated with semi-permanent changes in location. The pattern of daily movement is strongly skewed with >70% of flights being over distances of <10 km (Table 2). ...
Context 3
... day -1 , similar to the dis-tances travelled daily by Egyptian Geese in the present study. The longest daily distance recorded for a Grey Teal is 332 km (Roshier et al. 2006), exactly half the longest daily distance travelled by an Egyptian Goose (Table 2). A Comb Duck tagged in Malawi had a displacement distance of 655 km in 285 days, similar to displace- ment distances of Egyptian Geese from Barberspan (Cappelle et al. 2011). ...
Similar publications
Background:
The movement patterns of many southern African waterfowl are typified by nomadism, which is thought to be a response to unpredictable changes in resource distributions. Nomadism and the related movement choices that waterfowl make in arid environments are, however, poorly understood. Tracking multiple individuals across wide spatiotemp...
Citations
... Fidelity to individual moulting sites is high (>60% for a particular lake or pond, and >80% if waterbodies within 5 km on the same river system are considered the same "site"). During roaming periods, when they typically move across the landscape in small flocks after either aggregating to moult or pairing off to breed, Egyptian Geese are capable of anticipating variability in food resources and tracking patches of high food abundance in the local landscape and so seem to have high navigation capacity at a local (up to ~50 km) scale (Cumming et al., 2012;Henry et al., 2016;Ndlovu et al., 2013Ndlovu et al., , 2014. It remains unclear which movements are undertaken as individuals and which are in family groups or larger flocks. ...
Aim
Movement is integral to the distribution and abundance of wildlife. We undertook an experimental test of the navigation capacity of Egyptian Geese Alopochen aegyptiacus to better understand the movements of moult‐migratory waterfowl and the implications of navigation capacity for their ecology.
Location
Southern Africa. In June 2015, we translocated six post‐flightless moult Egyptian Geese 1250 km south, from north‐west South Africa (Barberspan) to the south‐west coast (Strandfontein). We compared their movements to those of 29 previously tracked resident Egyptian Geese from the source and translocation sites, and three additional sites (Voelvlei; Jozini Dam; Lake Manyame, north‐central Zimbabwe).
Methods
We used solar‐powered satellite GPS to track movement patterns and compared the movement paths of different birds using net‐squared displacement analysis and multiple regression analysis of different measures of movement paths.
Results
Over time periods up to 658 days, none of the translocated Egyptian Geese returned to Barberspan and only one appeared to fly towards it. Translocated birds showed some novel and risky behaviours. Longer, searching‐type movements were evident with the onset of both the breeding and moulting seasons. Quantitative comparisons suggested that translocated birds retained elements of learned behaviours.
Main conclusions
Navigation by Egyptian Geese appears to have a strong learned (internal) element, with long‐distance movement triggered by internal states such as the need to moult. Translocated animals modified their movement patterns in ways that mostly allowed them to survive. Our results have interesting implications for understanding the dynamics of individual populations; a strong reliance on learned behaviours may explain the unresolved conundrum of why no African duck species has colonized Europe without human assistance. Our analysis demonstrates the complexity of influences on animal movement and highlights the importance of navigation capacity for conservation biogeography.
... However, disturbances from stimuli such as human/vehicle noise and domestic dogs caused waterbirds to fly away from their feeding/resting patches (Tarakini et al., 2020a). Most duck species may often swim into the pan interior when sensing danger (Ndlovu et al., 2014). ...
Wetlands in southern Africa.
The formation and ecology of pans in southern Africa.
Waterbird communities and breeding in the pan ecosystem.
The pan ecosystem in western Zimbabwe - protected areas and nonprotected areas.
Trends and drivers of waterbird communities.
Threats to waterbirds inside and outside protected areas.
- Avian Influenza Virus (AIV)
- Avian malaria
- West Nile Virus (WNV).
Benefits of waterbirds to local people.
Measures for the conservation of waterbirds in the
pan wetland system.
... However, both species are commonly found at wetlands, and both may range far from open water to forage on agricultural fields. Both species also exhibit a relatively predictable daily movement sequence in most locations, with birds roosting overnight and foraging intensively in the morning and evening (Hockey et al., 2005;Ndlovu, Cumming, & Hockey, 2014). Their movements throughout the year can be divided into three main phases: (1) breeding, during which they are tied to a nest site and a nearby wetland until the ducklings can fly (duration around 10 to 15 weeks in total, with 4-5 weeks of incubation and 8-10 weeks for the ducklings to grow); ...
... (2) flightless molt, which involves synchronous replacement of the primaries at a deep, permanent wetland and takes 4-5 weeks every year (Milstein, 1993); and (3) a "roaming" period, during which the birds move around the landscape in flocks, following food resources in a seminomadic manner. Full analyses of the movements of both species have already been published Ndlovu, Cumming, Hockey, Nkosi, & Mutumi, 2013;Ndlovu et al., 2014). ...
Ecological theory predicts that if animals with very similar dietary requirements inhabit the same landscape, then they should avoid niche overlap by either exploiting food resources at different times or foraging at different spatial scales. Similarly, it is often assumed that animals that fall in different body mass modes and share the same body plan will use landscapes at different spatial scales. We developed a new methodological framework for understanding the scaling of foraging (i.e. the range and distribution of scales at which animals use their landscapes) by applying a combination of three well-established methods to satellite telemetry data to quantify foraging patch size distributions: (1) first-passage time analysis; (2) a movement-based kernel density estimator; and (3) statistical comparison of resulting histograms and tests for multimodality. We demonstrate our approach using two sympatric, ecologically similar species of African ducks with quite different body masses: Egyptian Geese (actually a shelduck), and Red-billed Teal. Contrary to theoretical predictions, the two species, which are sympatric throughout the year, foraged at almost identical spatial scales. Our results show how ecologists can use GPS tracking data to explicitly quantify and compare the scales of foraging by different organisms within an animal community. Our analysis demonstrates both a novel approach to foraging data analysis and the need for caution when making assumptions about the relationships among niche separation, diet, and foraging scale.
... We also referred to telemetry data (Cumming et al., 2012;Ndlovu et al., 2013), and the monthly bird counts of the Cape Bird Club (http://www.capebirdclub.org.za/countsstrandfontein) and Barberspan Nature Reserve to validate moult and breeding incidents for months in between our bi-monthly sampling periods. Africa outline map to clip off the sections of the buffer zone that overlapped with the ocean. ...
... It is not immediately clear why these birds delay moult for so long after breeding. Satellite telemetry results reported by Cumming et Ndlovu et al. (2013) revealed that even though most Egyptian geese and red-billed teal that moult at Barberspan and Lake Manyame (located in a summer-rainfall area in northern Zimbabwe at 17°49'S, 30°36'E) breed at distant locations (averaging 450 km and up to ≈1000 km away from the moulting site), these birds took at most a week to commute from their breeding sites to a moulting site. Although the lag period between breeding and moult differs significantly between Strandfontein and Barberspan, the timing of moult relative to peak rainfall was similar for both sites (Table 2). ...
Waterfowl flight-feather moult is expected to occur when energy is not needed for breeding and when a suitable safe habitat is available. Flight-feather regrowth is an energetically costly stage in the annual cycle of waterfowls. In this study, we tested the hypothesis that moult will coincide with the time of year when food and aquatic habitats are most abundant. We investigated how the timing of rainfall relates to the timing of breeding and flight-feather moult in five common southern African waterfowl at two sites in South Africa with opposite rainfall regimes (one summer, one winter). We then incorporated published data to compare and contrast the relative timing of breeding and moult in southern hemisphere (southern African and Australian) waterfowl with northern hemisphere (European and North American) species. Our results showed that southern African waterfowl breed in the wet season and moult during the dry season. Tadorna cana was an exception, breeding in the dry season and moulting during the wet season in the summer-rainfall area. There was also a long lag period between peak breeding and peak moult in southern hemisphere waterfowl species, the longest lag being that of birds in the summer-rainfall area. By comparison, northern hemisphere waterfowl species breed and moult during the warm season, with a shorter lag period between peak breeding and peak moult compared to southern hemisphere species. We concluded that waterfowl in southern Africa (with the exception of Tadorna cana), southeast Australia, Europe and North America time their breeding period to coincide with peaks in the availability of both food and breeding sites. Northern hemisphere species moult where chances of predation are low, when temperatures are warm, and before food and aquatic habitats approach their winter minima. By contrast, southern hemisphere waterfowl delay the onset of moult until the dry season, opting to moult when both food and aquatic moulting habitats are scarce.
... For Egyptian Geese the pattern was interpreted as early morning transit to the foraging grounds, followed by a late morning return to the roost site, followed again by late afternoon forage and subsequent return to roost site. These assumptions are supported by data from intensive field counts, from the same study sites, which show increases in numbers of loafing birds around the middle of the day (Ndlovu, Cumming & Hockey 2014). Start times for the model were therefore selected as representing foraging at 4 am, 6 am, 8 am, 2 pm, 4 pm and 6 pm. ...
... Longer-term adaptation or learning experience may be influencing their movements, including prior experience with resource distributions that effect dispersal strategies (Roshier et al. 2008b;Cumming et al. 2012;Ndlovu et al. 2013). For example, nomadic behaviour of Knob-billed Ducks was evident from our data. ...
... km, in contrast with Australian Grey Teal Anas gracilis that moved 2.9-25.2 km daily (Roshier et al. 2006) and Egyptian Geese Alopochen aegyptiaca in South Africa for which most daily movements (57%) were 1-10 km (Ndlovu et al. 2013). Thus, Knob-billed Ducks seem to explore far less frequently than those species, which may suggest greater reliance on their experience of the area or environmental cues affecting the frequency of their flights. ...
... Our results indicate that travel distances varied widely among the five waterfowl species that we studied, but there were key wetlands to which waterfowl have high site fidelity. Use of focal wetlands may be related to life stages when waterfowl are particularly vulnerable, such as during the moult (Ndlovu et al. 2013). ...
Habitat availability for Afrotropical waterbirds is highly dynamic with unpredictable rainfall patterns and ephemeral wetlands resulting in diverse movement strategies among different species. Movement strategies among waterfowl encompass resident, regional and intercontinental migrants, but little quantitative information exists on their specific movement patterns. We studied the movement ecology of five Afrotropical waterfowl species marked with satellite transmitters in Malawi, Mali and Nigeria. Resident species, including White-faced Whistling Ducks Dendrocygna viduata, Fulvous Whistling Ducks Dendrocygna bicolor and Spur-winged Geese Plectropterus gambensis, remained sedentary during the rainy season and only flew limited distances during other months. In contrast, Knob-billed Ducks Sarkidiornis melanotos made short regional movements >50 km in all months and showed little site fidelity to previously used habitats in subsequent years. Garganey Anas quequedula followed an intercontinental strategy and made long-distance jumps across the Sahara and Mediterranean to their Eurasian breeding grounds. Most species flew farthest during the dry season, as mean daily movements varied from 1.5 to 14.2 km and was greatest in the winter months (January–March). Total distance moved varied from 9.5 km for White-faced Whistling Ducks (October–December) to 45.6 km for Knob-billed Ducks (April–June). Nomadic behaviour by Knob-billed Ducks was evidenced by long exploratory flights, but small mean daily movements suggested that they were relying on previous experience. Improving our understanding of these movement strategies increases our ability to assess connectivity of wetland resources that support waterfowl throughout their annual cycle and focuses conservation efforts on their most important habitats. © 2015, Published in accordance with Title 17 U.S. Code, Chapter 1, Section 105.
... Egyptian goose movement patterns may be more related to prior experience and molting site requirements than by external forces such as rainfall and food availability (Cumming et al. 2012;Ndlovu et al. 2013Ndlovu et al. , 2014. Milstein (1993) suggested the key factor influencing habitat choice by Egyptian geese is safety from predators. ...
Egyptian geese (Alopochen aegyptiaca) occur in large numbers on golf courses in southwestern South Africa. They cause physical and financial damage to the courses and are a nuisance to golfers and golf course managers. Most control measures used to reduce the problem have been unsuccessful. We investigated the potential for environmental management options by determining which landscape features attract geese to certain areas within golf courses and cause them to avoid others. Goose vigilance levels were lower in use than in non-use areas regardless of group size (t1 = 5.837, P ≤ 0.001, F1 = 53.877, P ≤ 0.001). This behavior suggested that geese were attracted to some areas because they perceive them to be safer. Landscape features that attracted Egyptian geese were large open patches of lawn (>1.5 ha) and proximity to water bodies (<100 m). Water bodies should not be adjacent to open foraging or loafing areas. Other modifications may include planting herbaceous vertical vegetation around water bodies and open fairways to reduce habitat openness and predator visibility. Our results suggest that the level of the goose problem at any golf course is a consequence of the intrinsic properties of that course and not influenced by the extent of the problem at nearby golf courses. © 2014 The Wildlife Society.
... Egyptian goose movement patterns may be more related to prior experience and molting site requirements than by external forces such as rainfall and food availability (Cumming et al. 2012;Ndlovu et al. 2013Ndlovu et al. , 2014. Milstein (1993) suggested the key factor influencing habitat choice by Egyptian geese is safety from predators. ...
Egyptian geese (Alopochen aegyptiaca) occur in large numbers on golf courses in southwestern South Africa. They cause physical and financial damage to the courses and are a nuisance to golfers and golf course managers. Most control measures used to reduce the problem have been unsuccessful. We investigated the potential for environmental management options by determining which landscape features attract geese to certain areas within golf courses and cause them to avoid others. Goose vigilance levels were lower in use than in non-use areas regardless of group size (t 1 ¼ 5.837, P 0.001, F 1 ¼ 53.877, P 0.001). This behavior suggested that geese were attracted to some areas because they perceive them to be safer. Landscape features that attracted Egyptian geese were large open patches of lawn (>1.5 ha) and proximity to water bodies (<100 m). Water bodies should not be adjacent to open foraging or loafing areas. Other modifications may include planting herbaceous vertical vegetation around water bodies and open fairways to reduce habitat openness and predator visibility. Our results suggest that the level of the goose problem at any golf course is a consequence of the intrinsic properties of that course and not influenced by the extent of the problem at nearby golf courses. Ó 2014 The Wildlife Society. KEY WORDS Alopochen aegyptiaca, Egyptian goose, golf courses, habitat management, human-wildlife conflict, predator vigilance, South Africa, wildlife management.
