Nest Site Attendance Research Articles

Nesting attempts and success of Arctic-breeding geese can be derived with high precision from accelerometry and GPS-tracking

Sensors, such as accelerometers, in tracking devices allow for detailed bio-logging to understand animal behaviour, even in remote places where direct observation is difficult. To study breeding in birds remotely, one needs to understand how to recognise a breeding event from tracking data, and ideally validate this by direct observation. We tagged 49 adult female pink-footed geese (Anser brachyrhynchus) with transmitter neckbands in Finland in spring of 2018 and 2019, and in Svalbard in summer 2018, and validated inferences from tracking by field observations of nesting sites and family status in 2018–2020 (54 spring–summer tracks). We estimated nesting locations by taking the median coordinates of GPS-fixes at which the goose was motionless (overall dynamic body acceleration, ODBA < 1) on days with a daily median ODBA < 1, which approached the real nesting locations closely (within 1.6–3.7 m, n = 6). The start of nesting was defined as the first day on which the goose spent > 75% of time within 50 m of the nest, because nest site attendances steeply increased within one day to above this threshold. Nesting duration (number of consecutive days with > 75% nest site attendance) ranged between 3 and 44 days (n = 28), but was 30–34 days in confirmed successful nests (n = 9). The prolonged nesting of 39–44 days (n = 3) suggested incubation on unhatchable egg(s). Nest losses before hatching time occurred mostly in day 3–10 and 23–29 of nesting, periods with an increased frequency of nest site recesses. As alternative method, allowing for non-simultaneous GPS and accelerometer data, we show that nesting days were classified with 98.6% success by two general characteristics of breeding: low body motion (daily median ODBA) and low geographic mobility (daily SD of latitude). Median coordinates on nesting days approached real nest sites closely (within 0.8–3.6 m, n = 6). When considering only geographic mobility (allowing for GPS data only) nesting locations were similarly accurate, but some short nesting attempts were undetected and non-breeding tracks misclassified. We show that nesting attempts, as short as 3 days, and nesting success can be detected remotely with good precision using GPS-tracking and accelerometry. Our method may be generalised to other (precocial) bird species with similar incubation behaviour.

Multiple stressors including contaminant exposure and parasite infection predict spleen mass and energy expenditure in breeding ring-billed gulls

Daily energy expenditure (DEE) in animals is influenced by many factors although the impact of stressors remains largely unknown. The objective of this study was to determine how multiple physiological stressors (parasite infection and contaminant exposure) and natural challenges (energy-demanding activities and weather conditions) may affect DEE in nesting ring-billed gulls (Larus delawarensis) exposed to high concentrations of persistent organic contaminants (POPs). Physical activity, temperature, gastrointestinal parasitic worm abundance, relative spleen mass, plasma thyroid hormone levels and liver concentrations of POPs were determined; field metabolic rate (FMR) was used as a measure of DEE. For females, FMR was best explained by the percent of time spent in nest-site attendance and exposure to temperatures below their lower critical limit (65% of variation); 32% was also explained by relative spleen mass. In males, FMR was best explained by the number of hours spent in nest site attendance and either relative spleen mass or liver concentrations of tetra-brominated diphenyl ethers (tetra-BDEs) (55% of variation). Relative spleen mass, as an important factor relating to FMR, was best explained by models with a combination of parasite abundance (Diplostomum for females and Eucoleus for males) in a negative relationship, and liver POP concentrations (p,p′-DDE for females and tetra-BDEs for males) in a positive relationship (34%, 55% of variation for females and males, respectively). This study demonstrates that immune activity may be an important factor affecting energy expenditure in ring-billed gulls, and that contaminants and parasite abundance may have both a direct and/or indirect influence on FMR.

Field Metabolic Rate Is Dependent on Time-Activity Budget in Ring-Billed Gulls (Larus delawarensis) Breeding in an Anthropogenic Environment.

Environmental and behavioral factors have long been assumed to affect variation in avian field metabolic rate (FMR). However, due to the difficulties in measuring continuous behavior of birds over prolonged periods of time, complete time-activity budgets have rarely been examined in relation to FMR. Our objective was to determine the effect of activity (measured by detailed time-activity budgets) and a series of extrinsic and intrinsic factors on FMR of the omnivorous ring-billed gull (Larus delawarensis). The experiment was conducted during the incubation period when both members of the pair alternate between attending the nest-site and leaving the colony to forage in aquatic and anthropogenic environments (city, agricultural). FMR was determined using the doubly labeled water method. Time-activity budgets were extrapolated from spatio-temporal data (2-5 days) obtained from bird-borne GPS data loggers. Gulls had low FMRs compared to those predicted by allometric equations based on recorded FMRs from several seabird species. Gulls proportioned their time mainly to nest-site attendance (71% of total tracking time), which reduced FMR/g body mass, and was the best variable explaining energy expenditure. The next best variable was the duration of foraging trips, which increased FMR/g; FMR/g was also elevated by the proportion of time spent foraging or flying (17% and 8% of tracking time respectively). Most environmental variables measured did not impact FMR/g, however, the percent of time birds were subjected to temperatures below their lower critical temperature increased FMR. Time-activity budgets varied between the sexes, and with temperature and capture date suggesting that these variables indirectly affected FMR/g. The gulls foraged preferentially in anthropogenic-related habitats, which may have contributed to their low FMR/g due to the high availability of protein- and lipid-rich foods. This study demonstrates that activities were the best predictors of FMR/g in ring-billed gulls, thus providing strong support for this long-standing theory in bioenergetics.

Nest-site Attendance of the Resident White-tailed Sea Eagle (Haliaeetus albicilla) Outside the Breeding Season

The territorial pairs of White-tailed Sea Eagle are mainly sedentary and highly faithful to breeding territories and nest-sites. Due to a dramatic population decrease, many recent studies deal with the population status and habitat requirements of the species, but contemporary data on the nest-site attendance activity of the recovered population outside the breeding season are scarce. In the present study, we analysed the bonds of resident adult Sea Eagles with their nest-sites outside the breeding season (20 September – 20 February). We found that Sea Eagles actively attend their nest-sites during the non-breeding season, however, nest-site attendance varied between months, but not between years. Besides, almost half of the checked pairs repaired old or built new nests long before incubation, during September–December. We discuss the obtained results in the light of nest-site protection from forestry-related disturbance and propose to extend the protection of Sea Eagle nest-sites from above mentioned dis...

Nest temperature and parental behaviour of Arctic-breeding glaucous gulls exposed to persistent organic pollutants

Behavioural field observations are increasingly being used in ecotoxicological research to identify potential adverse effects of exposure to persistent organic pollutants (POPs). We investigated thermal conditions inside the nest and parental behaviour of glaucous gulls, Larus hyperboreus , breeding in the Norwegian Arctic in relation to the concentrations of major classes of POPs (organochlorines, brominated flame retardants and metabolically derived products) accumulated in their blood. Most notably, nest temperature was negatively correlated with the concentrations of the sum of (Σ) DDT, ΣPCB and several quantitatively minor POP classes within the incubating parent. To investigate the relationship between incubation ability and parental POP exposure further, we experimentally increased the costs of incubation by artificially increasing the clutch size from two to four eggs. Clutch enlargement was followed by a decrease in nest temperature, but this drop in temperature was not associated with POP concentrations within the incubating parent. However, males, which had higher POP concentrations and lower white blood cell counts than females, seemed less able to maintain nest temperature. There was virtually no evidence to suggest that ΣPCB or ΣDDT were associated with changes in the time a bird spent incubating. However, there was some indication that nest site attendance by nonincubating males was negatively related to ΣDDT, suggesting that nest protection may have been compromised. The results suggest that adverse effects of parental POP exposure may occur through suboptimal thermal conditions for embryo development and possibly increased egg predation risk.

Effects of rat odour and shelter on maternal behaviour in C57BL/6 dams and on fear and stress responses in their adult offspring

Recent studies in rats and mice suggest that developmental plasticity of HPA-stress and fear responses could be mediated by environment-dependent variations in maternal behaviour. The present study was designed to examine this question further by varying the adversity of the maternal environment to study its effects on nest-attendance and maternal care and on the HPA and fear responses in the adult offspring. C57BL/6 dams and their litter were housed in a cage system composed of a nest cage (NC) and a foraging cage (FC) connected by a tunnel. Using a 2 × 2 factorial design, we varied the maternal foraging environment (FC) by the presence or absence of rat odour (feces) and shelters (MouseHouse and tube) from postnatal days 1–14 and assessed the adult offspring's corticosterone response to isolation/novelty stress and their behaviour in three tests of fearfulness (elevated-O-maze, open-field, free exploration). While the presence of shelters in the FC reduced time spent in the NC (nest site attendance), the presence of rat odour in the FC increased active maternal care without altering nest site attendance. Alterations of the offspring's HPA and fear responses were rather subtle. The presence of shelters in the dam's foraging environment decreased fearfulness in the offspring in the free exploration test. In addition, males reared by dams exposed to rat odour were less fearful in the open-field test, and both males and females reared by dams without shelters and rat odour in the FC showed a greater corticosterone response to isolation/novelty stress. Multiple regression analysis indicated a negative relationship between maternal licking/grooming and fearfulness in males and a positive relationship between nest site attendance and fearfulness in females. Taken together, these results indicate that mouse dams adjust specific aspects of maternal behaviour in response to the specific properties of their environment, and that active maternal care and nest site attendance are two aspects of maternal behaviour that may affect the offspring's stress and fear systems independent of each other and in a sex-specific way.

Long and Short Trips in Nonbreeding Buller's Albatrosses: Relationships with Colony Attendance and Body Mass

Abstract Foraging strategies of nonbreeding seabirds attending colonies remain virtually unknown. Here we report the results of a satellite telemetry study of nonbreeding Buller's Albatrosses (Thalassarche bulleri) from the Snares island group south of New Zealand in 2000–2001. Two 6- to 7-year-old prebreeding birds dispersed to Tasmania, Australia, from late May until at least late July. Six older birds (five prebreeding birds, one former breeding adult) all adopted a dual strategy of short trips (mean duration 1.3 days, mean foraging range 129 km) and long trips to southern New Zealand (9.6 days, 871 km) or Tasmania (22.0 days, 1918 km). Time allocation to short trips increased with age and experience (both sexes) and nest-site attendance (males), and decreased during the guard (when the chick is attended) and late postguard (chick left unattended) stages (females). Up to the guard stage, most birds present at their colony on consecutive days foraged overnight (mean foraging range 101 km). Nonbreeding birds used the same foraging areas as breeding adults, but allocated more foraging time to short trips during the corresponding incubation period and early postguard stage, and to long trips during the guard stage. Results suggest that prebreeding birds explore foraging areas sequentially, and increase their time ashore by progressing from making only long trips, to introducing short overnight trips, to modifying the duration of and allocation between long and short trips. Changes in body mass recorded on Solander Island (160 km north of the Snares) show that experienced nonbreeding birds initiate long foraging trips to regain mass lost during short trips, and suggest that less frequent short trips (and hence fewer returns ashore) among inexperienced birds are related to less efficient foraging during long trips.

LONG AND SHORT TRIPS IN NONBREEDING BULLER'S ALBATROSSES: RELATIONSHIPS WITH COLONY ATTENDANCE AND BODY MASS

Abstract Foraging strategies of nonbreeding seabirds attending colonies remain virtually unknown. Here we report the results of a satellite telemetry study of nonbreeding Buller's Albatrosses (Thalassarche bulleri) from the Snares island group south of New Zealand in 2000–2001. Two 6- to 7-year-old prebreeding birds dispersed to Tasmania, Australia, from late May until at least late July. Six older birds (five prebreeding birds, one former breeding adult) all adopted a dual strategy of short trips (mean duration 1.3 days, mean foraging range 129 km) and long trips to southern New Zealand (9.6 days, 871 km) or Tasmania (22.0 days, 1918 km). Time allocation to short trips increased with age and experience (both sexes) and nest-site attendance (males), and decreased during the guard (when the chick is attended) and late postguard (chick left unattended) stages (females). Up to the guard stage, most birds present at their colony on consecutive days foraged overnight (mean foraging range 101 km). Nonbreeding b...

Plume Variation, Breeding Performance and Extra-Pair Copulations in the Cattle Egret

AbstractWe investigate how variation in breeding plumes influences pairing patterns, extra-pair copulations and breeding performance in the colonial cattle egret (Bubulcus ibis ibis). The breeding plumes of both male and female cattle egrets varied from almost none, to lush head, back and scapular plumes. Overall, male breeding plumes were longer and darker than those of females, but we observed the full range of plume development in both sexes. Plume development was positively correlated within breeding pairs. Females may be more selective in mate choice since they only paired with males with similar or better plumes and only accepted extra-pair copulations when the male had plumes that were greater than or equal to those of their mates. Males, in contrast frequently paired with females of lower plume development, and did not target well plumed females for extra pair copulations. Females may obtain direct benefits from pairing with well plumed males since these males copulated and fed chicks at a higher rate, although this did not lead to higher fledging success in our study. Well plumed females did not have higher nest attendance, nestling attendance, feeding rates or fledging success. Nevertheless, males appeared to invest more in a breeding attempt when paired to a well plumed female by increasing copulation rates, mate attendance and nest site attendance. Breeding plumes may therefore signal both parental and genetic quality to prospective mates.

Development of playback census methods for Storm Petrels Hydrobates pelagicus

The factors affecting the probability of nest site attendance and response to playback were examined on Mousa, Shetland, during 1996 with the aim of developing a standard method of censusing Storm Petrels using diurnal playback. Nest site attendance by breeding birds peaked at 90% during July. Site attendance by non-breeding birds was much lower at 15% and this increased as the season progressed. Studies of breeding phenology at colonies throughout Britain and Ireland demonstrated that the average laying dates at most colonies were in late June, but those at Mousa were on average two weeks earlier and at Inish Glora one week later. This analysis also suggested that site attendance is highest in mid-July and so this represents the best time of year to conduct playback censuses at colonies in Britain and Ireland. Rates of response to playback of the male purr call were highly variable, with evidence for effects of the environment, colony location, playback equipment and year. This suggests that the application of a single correction factor to playback survey data collected at different colonies is likely to result in serious errors in estimation of population status. We recommend that the probability of detecting a nest is examined during each survey so that a colony-specific correction factor can be applied to the census data.

Non-aggressive mate guarding by the blue-footed booby: a balance of female and male control

Thirteen pairs of blue-footed boobies (Sula nebouxii) were observed on their colony. Pairs courted frequently and, on average, copulated 24 times during the 30 days before laying, with 38% of those copulations occurring in the last 5 days (presumed fertile period). Males and females increased attendance at the nest site as laying approached. Seven females performed an average seven extra-pair copulations, with 1–2 paired male neighbors, but these were less concentrated in the presumed fertile period than within-pair copulations, and the last two copulations of all 7 females were with their social mates. Rates of female extra-pair copulations were six times lower when their social mate was present, and during the presumed fertile period, no female performed an extra-pair copulation in the presence of her mate. Males did not respond to infidelity of social mates with aggression, prompt copulation, retaliatory copulation, or increase in copulation. Seven of 13 males performed an average of five extra-pair copulations, with 1–3 paired female neighbors, before their own mates began egg-laying. The males' extra-pair copulations represented only 4% of their total copulations during their own mates' presumed fertile periods. Females, the larger sex, apparently control sexual access and copulate with extra males to achieve extra-pair fertilization. Males pursue a mixed strategy: they copulate with extra females, mostly outside their own mate's presumed fertile period, and they copulate increasingly with their social mate as laying approaches, probably assuring some paternity by mate guarding, involving attendance and courtship. Behavior of males and females is also consistent with other hypotheses for extensive joint nest site attendance: pairbonding, copulation access, and territory acquisition.

Effect of Wind on Field Metabolic Rates of Breeding Northern Fulmars

The field metabolic rate (FMR) of nesting Northern Fulmars (Fulmarus glacialis) was measured using the doubly labeled water technique. Although some labeled Northern Fulmars showed marked differences in behavior compared to controls. FMR did not change correspondingly. At—sea FMR averaged 1444 kJ/d, equivalent to 4.5 X basal metabolic rate (BMR). As a multiple of BMR it was independent of sex, wing length, body mass, mass change, and duration of the period at sea, but was strongly dependent on wind speed, being higher during slack winds. There was also a trend for higher wingbeat frequency at winds to low for sustained dynamic soaring. The high energetic cost of flapping flight during windless conditions may explain patterns of nest attendance: in particular, why nest site attendance by Northern Fulmars in winter is greater during calm weather. Lack of wind might limit the breeding range of this species and other Procellariiformes with high flapping—flight costs.

Copulation and Mate Guarding in the Northern Fulmar

I studied the timing and frequency of copulation in mated pairs and the occurrence of extra-pair copulation (EPC) among Northern Fulmars (Fulmarus glacialis) for 2 yr. Copulation peaked 24 days before laying, a few days before females departed on a prelaying exodus of about 3 weeks. I estimated that females were inseminated at least 34 times each season. A total of 44 EPC attempts was seen, 9 (20%) of which apparently resulted in insemination. Five successful EPCs were solicitated by females visiting neighboring males. Multiple copulations during a single mounting were rare within pairs but occurred in nearly half of the successful EPCs. Both sexes visited neighbors during the prelaying period, and males employed a special behavioral display to gain acceptance by unattended females. Males invested time in nest-site attendance during the prelaying period to guard their mates and pursue EPC. However, the occurrence of EPC in fulmars was largely a matter of female choice.