Great White Pelican Pelecanus Onocrotalus Research Articles

Experimental Biology in Conflict Resolutions: The Case of Pelicans and Cormorants in Israel

In Israel, which is a bottleneck for some six hundred million migrating birds, the drainage of the Hula Lake in the north resulted in serious conflicts between fish-eating birds and the intensive fish farming and agriculture that became established on the reclaimed land. Implementation of various deterrence methods, including lethal control, failed to solve these conflicts. We followed the concept that only by understanding the biology of the organism in question could the tools (indications) for effective and sustainable management be devised that would solve such conflicts while helping the preservation of natural assets such as wetlands and their inhabitants. We demonstrated this concept in the solutions reached in the case studies of pelicans and cormorants and their interactions with intensive commercial fish ponds. We studied the physiological condition, food preference and energy demands, and ecological constraints of Great White Pelican Pelecanus onocrotalus, Great Cormorant Phalacrocorax carbo and Pygmy Cormorant Microcarbo pygmeus. As a result, we suggested different management solutions that are currently implemented with the full cooperation of the fishermen and the nature preservation authorities. Based on assessment of visual acuity to detect and catch fish under water Great Cormorants were effectively pushed towards Lake Kinneret where they could hunt more profitable fish than in the turbid fish ponds. The established roosts there were not controlled such as to lead the birds away from the fishponds. In case of the pelicans, part of the drained Hula valley was reflooded and extra fish was provided. Both measures effectively reduced the damage at the fish farms. We have shown that such solutions are economically helpful for fishermen and enable the preservation of the wetland habitat.

Confidence intervals and sample size for estimating the prevalence of plastic debris in seabird nests

Evidence is accumulating about the impacts of plastics on marine life. The prevalence of plastics in seabird nests has been used as an indicator of levels of this pollutant in the ocean. However, the lack of a framework for defining sample sizes and errors associated with estimating the prevalence of plastic in nests prevents researchers from optimising time and reducing impacts of fieldwork. We present a method to determine the confidence intervals for the prevalence of debris in seabird nests and provide, for the first time, information on the prevalence of these items in nests of the Hartlaub’s gull Larus hartlaubii, the African penguin Spheniscus demersus, the great white pelican Pelecanus onocrotalus, and the white-breasted cormorant Phalacrocorax lucidus in South Africa. The method, based on observations and resampling simulations and tested here for nests of 12 seabird species from 15 locations worldwide, allows for straightforward hypothesis testing. Appropriate sample sizes can be defined by combining this method with a Bayesian approach. We show that precise estimates of prevalence of debris in nests can be obtained by sampling around 250 nests. Smaller sample sizes can be useful for obtaining rough estimates. For the Hartlaub’s gull, the African penguin, the great white pelican, and the white-breasted cormorant, debris were present in 0.75%, 3.00%, 6.41%, and 25.62% of the respective nests. Our approach will help researchers to determine errors associated with the prevalence of debris recorded in seabird nests and to optimise time and costs spent collecting data. It can also be applied to estimate confidence intervals and define sample sizes for assessing prevalence of plastic ingestion by any organism.

Changes in the waterbird community of the Parc National du Banc d’Arguin, Mauritania, 1980–2017

SummaryThe Parc National du Banc d’Arguin in Mauritania hosts the largest concentrations of coastal waterbirds along the East Atlantic Flyway. In spite of this importance, a review of the changes in the numbers of waterbirds in the area is lacking since the first complete count in 1980. Here we analysed the seven complete waterbird counts made since then, and the additional yearly counts made in one subunit (Iwik region) since 2003. We present evidence for changes in the community composition of waterbirds over the past four decades. Total waterbird numbers showed a decrease between 1980 and 2017, with only Great White Pelican Pelecanus onocrotalus showing a significant increase in numbers. Five species showed significant declines: Long-tailed Cormorant Phalacrocorax africanus, Red Knot Calidris canutus, Bar-tailed Godwit Limosa lapponica, Eurasian Curlew Numenius arquata, and Western Marsh Harrier Circus aeruginosus. In the remaining species, the variation in numbers between counts was too large, and the number of complete counts too small, for trends to be detected. The yearly counts at Iwik region also showed sharp decreases in the numbers of Red Knot, Bar-tailed Godwit, and Marsh Harrier, but not of Long-tailed Cormorant and Eurasian Curlew. A multivariate analysis revealed a significant change in species composition over time, which was caused mainly by changes in the species depending on the intertidal mudflats for feeding (generally in decline) vs. the species depending on fish and crustaceans in the sublittoral and offshore zones (often showing increases).

Autumn Passage of Soaring Birds over Dobrogea (Romania): A Migration Corridor in Southeast Europe

The Dobrogea region in southeastern Romania, which is part of the Eurasian-East African Flyway, is listed as one of the important migration corridors for soaring birds on the western coast of the Black Sea. However, our knowledge regarding migration intensity, phenology and geographical patterns of soaring birds over the area is poor. To determine the migration intensity and phenology of soaring birds, we recorded the autumn migration in the Măcin Mountains (northern Dobrogea) from mid-August to the end of October between 2002–2007. To describe the geographical patterns of migration at a regional scale, we recorded migration intensity in the second half of September in 2010 and 2011, simultaneously from 15 and 13 counting points, respectively, covering the entire region of Dobrogea. In the Măcin Mountains we recorded a mean number (±SD) of 11,297 ± 2333.5 (CV = 20.7%) migrating raptors per year, and of 21,367 ± 10,949.3 (51.2%) and 455.6 ± 43.6 (9.6%) migrating White Storks Ciconia ciconia and Black Storks Ciconia nigra, respectively. Migration phenology parameters varied across raptor and non-raptor species. Migration occurred over a broad front, covering all of Dobrogea. However, migration intensity was more pronounced in the western, central and eastern parts of the region, and was less intensive in the northern central areas. Overall, we recorded 30 migrating raptor species and three non-raptor species. The most abundant raptors were Common Buzzard Buteo buteo, European Honey Buzzard Pernis apivorus, Lesser Spotted Eagle Clanga pomarina, Eurasian Sparrowhawk Accipiter nisus and Western Marsh Harrier Circus aeruginosus. The three non-raptor species were White Stork, Black Stork and Great White Pelican Pelecanus onocrotalus. Our study provides the first general overview of the autumn passage of soaring birds over Dobrogea, highlighting the importance of this area as part of a global migration network.

Autumn migration of soaring birds through the Gebel El Zeit Important Bird Area (IBA), Egypt, threatened by wind farm projects

SummarySystematic bird observations were performed during autumn 2006 in the migration bottleneck area of Zeit Bay, Egypt (27.73°N, 33.51°E), situated on the coast of the Gulf of Suez, opposite southern Sinai. Owing to the strong northerly winds in that area, considerable pressure exists to construct wind farms. A total of 145,432 soaring birds, including 134,599 storks and 9,376 raptors over a period of 453.6 hours were observed between 20 August and 29 October by two teams working daily in two shifts. White Stork Ciconia ciconia and European Honey Buzzard Pernis apivorus were the most numerous species (91.4% and 5.7% respectively) of all soaring birds observed. As both species migrate early, relatively few birds were recorded passing through in October. A total of 57,179 soaring birds were observed within a range of 2.5 km from the observers, and of these 32,248 were flying at heights up to 200 m. Few individuals of the rapidly declining breeding populations of Egyptian Vulture Neophron percnotperus (‘Endangered’) and Lesser Kestrel Falco naumanni (‘Vulnerable’) passed (8 and 33 respectively). Pallid Harriers Circus macrourus (‘Near Threatened’) however, were more numerous (100) than at other migration sites along the East African-West Asian Flyway (Israel, southern tip of Sinai, Suez and Bab-el-Mandeb). Western Marsh Harrier Circus aeruginosus and Montagu’s Harrier Circus pygargus were also more numerous than at these sites. Some other large migrant species, observed at Suez, Bab el-Mandeb or in Israel, were seen only in small numbers or not at all at Zeit Bay in autumn. Among them, the Steppe Eagle Aquila nipalensis being the best known example of loop migration, entering Africa at Suez and Bab el-Mandeb, is for this reason not expected in autumn at Zeit Bay, while in spring it is a regular migrant. The number of Black Storks Ciconia nigra observed accounted for 4.8% of the flyway population, that of White Storks for 33.3%, Great White Pelicans Pelecanus onocrotalus for a further 3.5% and European Honey Buzzards for 0.8%. The extrapolation of the number of birds passing through the study area during the migration season, suggests that it was used by 92% of the White Stork, 12% of the Black Stork, 5% of the Great White Pelican, 4% of the European Honey Buzzard and 2% of the Pallid Harrier flyway populations in autumn 2006.

Numbers and distribution of the Great White Pelican Pelecanus onocrotalus and the Pink-backed Pelican P. rufescens in north-eastern KwaZulu-Natal, South Africa

KwaZulu-Natal (KZN), South Africa, is the most southerly area in Africa in which the Pink-backed Pelican Pelecanus rufescens breeds. This area also boasts the most southerly breeding colony on the eastern seaboard of Africa for the Great White Pelican P. onocrotalus. Considerable amounts of data relating to the distribution and numbers of these two species in north-eastern KZN have been collected in a variety of ways by a number of people. These data were collated to estimate the distribution and status of the two pelican species and to evaluate any trends. There is no evidence of contraction or expansion in the distribution of either species. Numbers in south-eastern Africa are estimated to be 6 000–9 000 for the Great White Pelican and 600–900 for the Pink-backed Pelican. Numbers of both species were highly variable at the main locality, Lake St Lucia. For their long-term conservation it is necessary to take into account that neither population is restricted to the study area and that there are fluctuations in their distributions and numbers.

Trends in numbers of Kelp Gulls Larus dominicanus off western South Africa, 1978–2007

The number of Kelp Gulls Larus dominicanus breeding at 11 islands in South Africa's Western Cape province increased during the period 1978 to 1999–2000 and then decreased. The increase came after removal of controls on gulls and was associated with supplementary food provided by fish factories and rubbish tips. The decrease resulted from predation of gull chicks at some colonies by an increased population of Great White Pelicans Pelecanus onocrotalus. At Dassen Island, the density of gull nests remained constant as the colony doubled, but decreased by 50% as the colony decreased. At Dassen and Schaapen islands, the clutch size increased after pelicans started eating chicks. Numbers of gulls at two southern colonies where pelicans are seldom encountered have increased recently. This may have been influenced by shifts to the south and east of several fish stocks and their associated fisheries.

Breeding incidence of the Great White Pelican Pelecanus onocrotalus and the Pink-backed Pelican P. rufescens in south-eastern Africa from 1933 to 2005

The Great White Pelican Pelecanus onocrotalus and the Pink-backed Pelican P. rufescens are flagship species for the Greater St Lucia Wetland Park, north-eastern KwaZulu-Natal, South Africa. The traditional breeding sites for the Great White Pelican and the Pink-backed Pelican are confined to Lake St Lucia and Nsumo Pan, respectively. Considerable amounts of data have been collected since 1933 relating to the breeding efforts of these populations, and these data have been collected in a variety of ways. This study represents an attempt to collate and summarise these data and to make some estimations of the breeding success of the two pelican species in south-eastern Africa. Breeding attempts of Great White Pelican have been erratic and have had varied success. Although less erratic, only small numbers of the Pink-backed Pelican have bred.

Foraging behaviour and energetics of Cape gannets Morus capensis feeding on live prey and fishery discards in the Benguela upwelling system

We compared the foraging ecology of Cape gannets Morus capensis attending 2 colonies of equivalent size, yet with contrasting diet and population trends. One colony, on the west coast of South Africa, is decreasing in size and its occupants feed mainly on fishery wastes, whereas the other colony, on the south coast of South Africa, is growing and its occupants feed exclusively on natural prey (pelagic fish). In October and November 2005, we examined the diet, at-sea behaviour, and energy requirements of breeding gannets using direct observations, miniaturised GPS loggers, and time-depth recorders attached to foraging adults. Concurrent hydroacoustic surveys allowed us to assess the distribution and abundance of their preferred prey (the sardine Sardinops sagax and anchovy Engraulis encrasicolus). Birds from the declining west coast colony foraged in areas contain- ing very low abundances of pelagic fish. They fed primarily on low-energy fishery discards. They increased their foraging effort and exploited a greater area than birds from the growing colony, which took advantage of abundant pelagic fish stocks in their foraging range. A marked eastward shift of pelagic fish initiated in the late 1990s has resulted in the shortage of natural prey to Cape gannets on the west coast, strongly suggesting that the local population trend is driven by food avail- ability during the breeding season. A bioenergetic model showed that enhanced availability of low- energy fishery discards does not seem to compensate for the absence of natural prey. Added to the predation pressure by the Cape fur seal Arctocephalus pusillus and the great white pelican Pelecanus onocrotalus, those threats weigh heavily on a vulnerable seabird population.

Status of pelicans and cormorants on the northern Black Sea

The status of breeding pelicans and cormorants is assessed in the area from the Danube delta (Romania) to the northern part of the Crimean peninsula. Four breeding species occur in inland and coastal wetlands: Dalmatian Pelican Pelecanus crispus, Great White Pelican Pelecanus onocrotalus, Great Cormorant Phalacrocorax carbo and Pygmy Cormorant Phalacrocorax pygmeus. Data on clutch size and breeding success are given. Historically, all four species were restricted to the Danube delta. Currently, with the exception of Dalmatian Pelican, they all breed successfully on the eastern Black Sea coast in the Ukraine. There are many conservation problems that will jeopardize the breeding of these species in the future if nothing is done.

The physiological state of captive and migrating Great White Pelicans ( Pelecanus onocrotalus) revealed by their blood chemistry

The Great White Pelican Pelecanus onocrotalus is an endangered migratory bird, threatened by diminishing natural feeding sites and by persecution by fishermen. The majority of the migrating White Pelican (71 000) stop-over in Israel during their autumn migration to Africa. As part of a larger study, aimed to assess the necessity of feeding during the stop-over in Israel, we examined the blood chemistry of captive and migrating White Pelicans. Blood was sampled from captive birds maintained on a fish diet, after food deprivation for 48 h and from wild birds brought from the field during migration. Food deprivation resulted in increased plasma levels of triglycerides and in lower levels of urea, potassium and calcium. In migrating birds, increased plasma levels of urea and CPK and lower levels of creatinine were revealed. In general, the coefficient of variation in the blood chemistry of migrating pelicans was higher than in the captive birds, that is to say, that these birds were in a variable physiological condition. The blood profile of migrating and wintering pelicans did not indicate a state of dehydration but did indicate energy deficiency. The less extreme changes in blood chemistry of the 48 h food-deprived compared to migrating pelicans suggest that the former did not reach a state of starvation. We conclude that for White Pelicans the stop-over in Israel is a must in order to rest and replenish their fuel reserves for completion of their autumn migration to Africa.

The energetic demand of the Great White Pelican during migration in Israel and its implication to the conflict between fish industry and pelicans

Shmueli, M., Arad, Z., Izhaki, I. & Crivelli, A. 2000. The energetic demand of the Great White Pelican during migration in Israel and its implication to the conflict between fish industry and pelicans. Ostrich 71 (1 & 2): 1. The Great White Pelican Pelecanus onocrotalus is a migrating bird, which is an endangered species. The majority of the western Palaearctic populations stopover in Israel during their autumn migration (71 421 ± 127 individuals per year). Although most of these birds are transient over Israel, an increasing number of individuals (1 142 ± 882, between 1990–1994) stay and winter in the northern part of Israel. The natural feeding sites for pelicans diminished during recent decades due to human activities, and the aquaculture sites of intensive fishery became their favourite feeding places either during migration or during winter. The fish industry reports huge damages to fish yield. This study tried to assess ecophysiological needs of the White pelicans during migration and wintering in Israel, and to evaluate the necessity for pelicans to feed in Israel on their route to east-central Africa. The study combines laboratory measurements of energy consumption of captive pelicans, and field observations of migrant and wintering pelicans, and satellite tracking of migrating pelicans. The mean mass-specific metabolic rate (BMR) of the pelican was 236 kJ/(kg*day), without significant differences between sexes or diets (fish or chicks) and seasons: digestible energy intake (DEI) was 490–730 kJ/(kg*day) also without significant differences between sexes and diets. Wet food consumption (WFC) was greater on the fish diet (1.120 kg/day per bird) than on the chick diet (0.970 kg/day). Digestive efficiency was higher on the fish than on the chick diet (86% and 77%, respectively). Fat deposition in dead migrant pelicans during autumn, was 290 g (3.4% + 2.6% of body mass, n = 81). Fat deposition in wintering pelicans was significantly higher (5.4% ± 3.4% of body mass, n = 21). From these data, the average flight range of transient pelicans was estimated as 1 120 km without refueling. Although satellite records gave us information on the northward migration routes of pelicans from Israel, we need further information about the precise area of the pelicans in Africa. Nevertheless it is concluded that pelicans need to feed during their stopover in Israel, or at some unknown feeding sites along their southward migratory route, to complete their journey to their wintering grounds in east-central Africa. The results of this research should contribute to the establishment of new management policies, to the solution of conflict with the fish industry and to the conservation of pelicans in Israel.

Hand‐rearing the Eastern or Great white pelican Pelecanus onocrotalus at Vogelpark Avifauna, Alphen

The Eastern or Great white pelican Pelecanus onocrotalus is rarely bred in captivity and eggs are often infertile, or are broken or disappear during nesting. At Vogelpark Avifauna, Alphen, mortality of parent‐reared young has been high and some chicks have drowned because they could not climb out of the pond in the outdoor enclosure. Between 26 January and 26 April 1996 52 eggs were laid, only four (8%) of which were fertile. The eggs were removed from the nests and placed in an incubator which was maintained at 37.6°C. The eggs hatched on 26 April, 1, 18 and 19 May. This paper describes incubation, hand‐rearing, diet and development of the hatchlings.

Conservation of an increasing population of great white pelicansPelecanus onocrotalusin South Africa's Western Cape

Unlike many pelican populations, that of the great white pelican Pelecanus onocrotalus in the Western Cape, South Africa, has increased in size, from 20–30 pairs in the first half of the century to over 500 in 1993. The population increase in the past 10 years was too fast to be explained solely by breeding production; immigration also may have been involved. Increased number of coastal water bodies, some stocked with introduced fish, availability of agricultural offal, and lack of disturbance at the breeding site on Dassen Island likely contributed to the population increase. Dassen Island and a number of the coastal water bodies where pelicans roost and forage in the Western Cape are now proclaimed nature reserves. It is suggested that the few important water bodies not yet afforded legal protection should also be proclaimed. Research is needed on the role of offal in the diet and to show whether there has been immigration of pelicans from areas outside the Western Cape.

PRELIMINARY DATA ON THE IMPORTANCE OF ISRAEL FOR THE CONSERVATION OF THE WHITE PELICANPELECANUS ONOCROTALUSL.

Summary Izhaki, I. 1994. Preliminary data on the importance of Israel for the conservation of the White Pelican Pelecanus onocrotalus L. Ostrich 65:213-217. The majority of the western Palaearctic populations of the Great White Pelican Pelecanus onocrotalus stop over in Israel during their autumn migration. The annual average number of pelicans observed over Israel in autumn was 71,421±5,027. Although most of these birds were transient over Israel, increasing numbers of individuals (1130±303, between 1990 and 1993) stay and winter in the northern part of Israel. The natural feeding sites for pelicans were diminished during recent decades due to human activities such as the drainage of the Hula swamp in northern Israel 40 years ago. However, intensive fishery and aqua-culture sites became their favourite feeding laces either during migration or in winter. The fish industry complained that the birds seriously affect fish yield. The pelicans not only cause direct damage to the fix industry by predation, but ...

Where do Palaearctic Great White Pelicans (Pelecanus onocrotalus) presently overwinter?

The population of Great White pelicans Pelecanus onocrotalus breeding in the Palaearctic (from Greece to the USSR) is estimated at more than 10 000 pairs. This species has, however, been very little studied and the restricted amount of ringing carried out on this bird has not greatly improved our knowledge of its migration routes and wintering areas. Counts have been carried out during the autumn migration period over several years at three different sites (Greece, Bulgaria and Israel) and the migration routes, the stopover sites and the numbers of birds can now be described with precision. By using a motorized glider, migrating pelicans could be followed from the north to the south of Israel in a single day, the average speed could be estimated and further information on the flight capabilities could be obtained. After the discovery of very high numbers during the migration period, the hypothesis has been advanced that non-breeding Great White pelicans do not remain on their wintering grounds, but return each spring to oversummer in the Palaearctic. The majority of the population of Great White pelicans breeding in the Palaearctic used to winter in the Nile delta (Egypt) at the start of this century. Because of the numerous developments carried out in the delta, however, they no longer winter there and they have been forced to find another wintering area further south. Unfortunately, this new site is still unknown and several hypotheses are proposed. Finally we recommend that movements be monitored by satellite in the future in order to discover the new wintering site(s) of this species and to confirm the correctness of the migration routes described in this study.

Energy requirements of a Great white pelican (Pelecanus onocrotalus) population and its impact on fish stocks

The Great white pelican Pelecanus onocrotalus is a major predator of some freshwater fish stocks in much of Africa. Detailed population time‐activity budgets allowed us to estimate that the south‐western Cape Province population consumed 184 tonnes offish annually. Of this, 69% was required for adult existence, 17% for chicks and 14% for flight. Per capita consumption averaged 840 g per day, or 8–8% of body weight; very much less than the figure of 17–6% used in some energy budget calculations. Our integrative bioenergetics approach lends some support for the use of 10% of body weight as the amount of food consumed per day by large piscivorous birds for initial estimates of their impact on stocks.Predation by Great white pelicans may account for some 10–25% offish production, a shortage of reliable data on fish production in African freshwater ecosystems makes a more precise estimate impossible. Food supplies and shoreline length may both be important factors for pelican populations.

THE BREEDING OF THE GREATER FLAMINGO AND GREAT WHITE PELICAN IN EAST AFRICA

SummaryThis paper brings together observations on the breeding of the Greater Flamingo Phoenicopterus ruber and Great White Pelican Pelecanus onocrotalus, mainly at Lake Elmenteita, Kenya, 1951–1971.The Greater Flamingo bred at Lakes Elmenteita and Nakuru in 11/21 observed years and at Lakes Natron and Magadi in 5/12 observed years. On average, it breeds about every second year, but a succession of breeding years is followed by several years in which no breeding occurs.A history of 21 years' breeding at Lakes Nakuru and Elmenteita is given. At Elmenteita three sites have been used, the main site in every breeding year, the others less often. The number of pairs breeding in any year has varied from 500–9,250, but in 1968 flamingos bred three times, involving perhaps 8,500 pairs which made about 15,700 nests, some pairs perhaps laying twice or even thrice in a year.Losses of eggs (38.2% overall) were caused by rising water (16.2%), competition for nest space with Great White Pelicans (6.9%, after 1968 only), human interference (3.5%), Marabou Stork predation (1.8%) and other natural causes (9.8%).Losses among chicks totalled 68.3% overall and were mainly due to Marabou Storks (36.5%), undiagnosed disease (8.6%), and rising water (6.6%). Disease caused serious loss only in 1966, and after 1968 losses from Marabous rose from 2.7% to 76.5%, resulting in an increase in overall mortality from 48.7 to 92%. This was perhaps associated with the establishment of a fish factory at Lake Naivasha.When attacking flamingo colonies Marabous did not actually eat many eggs or chicks, but simply caused wholesale desertion by alarming the flamingos. In 1968 total desertion of a colony of 4,500 pairs was caused between 18 and 26 March by a maximum of 17 Marabous, and similar wholesale desertion was caused in later years.The overall breeding success among Greater Flamingos at Elmenteita was about 19% of eggs laid, but without the excessive post‐1968 Marabou predation would have been about 30%. At such a rate Greater Flamingos require at least 24 years of adult life to replace themselves, but if the mortality caused by Marabous since 1968 continues they will require about 58 years, and the population will inevitably decline. Breeding success at Lakes Magadi and Natron has been higher, about 44% of eggs laid; but figures available are much more approximate than at Elmenteita.Some new data on display, nest‐site selection, laying dates, clutch‐size, hatching and creche behaviour are given for the Greater Flamingo.The Great White Pelican bred at Lake Elmenteita from 1968 to 1971 without a break, some birds laying in every month, but with reduced laying November–December. They bred on the same islands as, and in association with the Greater Flamingo, and caused heavy losses among the latter, not through aggressiveness, but simply because of their superior size and weight.Although food supply must ultimately have controlled the pelican's ability to breed, an adequate food supply was available for 6 years before they did and continued after they had ceased. Their breeding was finally triggered by the Greater Flamingo colonies, with which the pelicans associated. When a flamingo colony was deserted because of Marabou Storks the pelicans, unafraid themselves of the Marabous, also deserted. They also associated with, and wiped out, a colony of Sacred Ibis.From July 1968 to June 1969 about 2,600 pairs of pelicans bred at Elmenteita, rearing about 2,200 young to the flying stage. The breeding colony apparently comprised most of the adults from Lake Nakuru and Lake Naivasha, the main feeding areas.From July 1968 to January 1971 certainly 7,200 and probably 8,000 pairs of pelicans bred at Elmenteita. Some pairs may have bred twice or thrice in this period. Breeding ceased suddenly in January 1971, eggs, and small and large young being alike abandoned for no established reason, although food supply was certainly still plentiful.Additional information on pair formation, incubation and fledging periods, nest‐relief, etc. is given. The best available record of the incubation period is 35–36 days. Nest relief takes place on average about once every 48 hrs, and is dependent on thermal activity enabling the pelicans to soar.At Elmenteita large young ate quantities of putrefying matter, including the corpses of other young pelicans. They also ate living young hatching from eggs, and up to 14 days old. Touch probably plays an important part in helping them to locate possible food in opaque water.