Nest Failure Research Articles

Nest raiding by bonnet macaques (Macaca radiata) and the response of nest guarding birds in a suburban habitat.

In many primate species, nest raiding is a form of opportunistic foraging behavior designed to acquire protein-rich eggs and nestlings. In urban environments, this is a significant cause of nest failure in birds. Here, we describe nest raiding and egg predation in bonnet macaques (Macaca radiata) inhabiting a suburban area of Salem, Tamil Nadu, India. During nest raiding, large-billed crows (Corvus macrorhynchos) and house crows (Corvus splendens), actively defended their nest from the macaques. When several macaque foragers jointly raided the nest, they were successful in obtaining and consuming the eggs. In contrast, when a solitary macaque attempted to raid the nest, it was unsuccessful. Bird size appeared to play an important role in nest defense. Small birds, such as the scaly breasted munia (Lonchura punctulata) and the purple sunbird (Cinnyris asiaticus) were not able to protect their nests from lone bonnet macaques. These observations indicate that in urban landscapes, bonnet macaques are egg predators of many bird species. When macaques coordinate their actions and forage in small subgroups, they were more successful in preying on the eggs of larger-bodied bird species.

Nest Box Cameras Provide Insight into Causes of Nest Failure for American Kestrels

ABSTRACT Although nest failure is a common occurrence in birds, oftentimes the causes, or details, of the failure are unknown because nests cannot be monitored closely or continuously. This inability to monitor nests in ways that allow for a detailed understanding of nest failure can hamper our ability to conserve declining species, such as the American Kestrel (Falco sparverius). Here we describe previously unreported observations from continuous video monitoring in kestrel nest boxes and biweekly nest monitoring via an extendable fiber optic endoscopic camera. From continuous video monitoring we observed adult kestrels consume a kestrel egg with little to no development and a European Starling (Sturnus vulgaris) pierce and remove an abandoned kestrel egg from a nest box. From biweekly monitoring with a fiber optic camera, we inferred that nest abandonment by kestrels was associated with eggs not developing either from infertility or early-stage embryo death. Although it is unclear how common such occurrences may be across the broader range of kestrels, these observations may provide impetus to explore these causes of nest failure more closely.

The Evolution of Mate Attachment.

AbstractWhether natural selection leads to attachment in monogamous pair bonds has seldom been addressed. Operationally defining attachment as a behavioral modifier that decreases divorce probability with pair duration, we develop a model for the evolution of attachment. If divorce (the ending of a pair bond when both individuals survive to the next breeding season) is more likely to occur out of poor-quality reproductive opportunities (i.e., poor territory or low-quality mate), individuals in experienced pairs are more likely to be found in high-quality opportunities. Consequently, when divorce decisions occur using imperfect information from reproductive success, pair duration provides individuals with information about the quality of their reproductive opportunity and attachment can evolve. We show that high survival rates, divorce propensities, and probabilities of nest failure favor the evolution of attachment. Attachment is also more likely to evolve when individuals can directly assess the quality of their reproductive opportunity (as opposed to relying on imperfect information from reproductive success), when the quality of the reproductive opportunity has adult survival ramifications, and when divorce coevolves with attachment. We show that our core conclusions are robust to a variety of assumptions using individual-based simulations. Our results clarify how attachment can be adaptive and suggest that studying pair bonds as dynamic entities is a promising avenue for future work.

Nest site vegetation structure influences nest predators and nesting success of understory birds in a dry evergreen forest in northeastern Thailand

Abstract Nest predation is typically the main cause of nest failure in forest understory birds; thus, identification of primary nest predators is key to understanding nest predation patterns. Furthermore, responses of predators are likely affected by vegetation structure, but predator responses to micro-scale habitat characteristics are largely unknown, especially in tropical forests. We used a long-term study with one of the largest datasets of its kind to investigate the extent to which micro-habitat structure (5-m radius surrounding a nest) can predict the likelihood of predation and by which predator. In a secondary evergreen forest in northeastern Thailand, 2013–2021, we found 1,016 active nests of 13 species and 24-hr video-monitored 500 of them. We recorded 336 predation events from 16 nest predator species. From this and previous studies at our site, we identified the top 4 predator species/species-groups accounting for ~83% of predation events: Macaca leonina (northern pig-tailed macaque, 36% of predation events), cat snakes (Boiga cyanea [green cat snake] and Boiga siamensis [grey cat snake]) (20%), Lycodon cf. davisonii (Blandford’s bridle snake, 18%), and accipiters (A. trivirgatus [Crested Goshawk] and A. badius [Shikra]) (9%). These 4 predator species differed in their responses to vegetation structure likely reflecting differences in foraging behaviors. Macaque and accipiters, both diurnal and visually-oriented, tended to depredate more visible/open nests, but macaques depredated nests surrounded by more trees and short woody stems (<3 m tall) compared to raptors. For snakes, both nocturnal, cat snakes depredated nests with higher numbers of both short woody stems and woody climbers, whereas bridle snakes depredated nests with more trees and fewer climbers. As noted previously, nest predator identity is critical to understanding habitat-predation patterns. Our data suggest that nest site vegetation characteristics influence the likelihood of a given species of predator locating a nest and that even small changes in vegetation structure could significantly alter predation patterns.

Songbird annual productivity declines with increasing soil lead contamination around nests

Abstract Songbirds incidentally ingest soil contaminated with lead and several species in the Southeast Missouri Lead Mining District have a negative relationship between soil lead concentration and reproduction. We used an individual-based model (IBM) to simulate nesting processes throughout the breeding season to estimate annual productivity for 5 songbirds in relation to soil-lead concentration. We modeled daily nest survival and number fledged in relation to soil lead and incorporated these relationships into the IBM using a Bayesian approach that fully captured parameter uncertainty and process variation. The proportion of the posterior distribution for the effect of soil lead on daily nest survival was mostly negative for Pipilo erythrophthalmus (Eastern Towhee), Passerina cyanea (Indigo Bunting), Cardinalis cardinalis (Northern Cardinal), Sialia sialis (Eastern Bluebird; f = 0.972, 0.990, 0.741, 0.581, respectively), and slightly positive for Spizella pusilla (Field Sparrow; f = 0.680). The proportion of the posterior distribution for the effect of soil lead on the number fledged from successful nests was mostly negative for S. pusilla, P. erythrophthalmus, and C. cardinalis (f = 0.867, 0.585, 0.508, respectively) and positive for P. cyanea and S. sialis (f = 0.773, 0.744). Simulated annual productivity decreased by 0.04–1.47 young/female/year among species across the range of soil lead concentrations, with the greatest declines for P. erythrophthalmus and P. cyanea. The probability of fledging one or more young changed from 51% to 15% for P. erythrophthalmus, 57% to 23% for P. cyanea, 60% to 48% for C. cardinalis, 94% to 84% for S. sialis, and 57% to 64% for S. pusilla as soil-lead concentration around a nest increased from 20 to 4,000 ppm. Most nest failures were the result of predation; therefore, we suggest lead may have affected birds’ behavior at the nest, or affected nest site quality, which resulted in higher nest predation.

Androgen and glucocorticoid profiles throughout extended uniparental paternal care in the eastern hellbender salamander (Cryptobranchus a. alleganiensis)

The behavioral endocrinology associated with reproduction and uniparental male care has been studied in teleosts, but little is known about hormonal correlates of uniparental male care in other ectotherms. To address this gap, we are the first to document the seasonal steroid endocrinology of uniparental male hellbender salamanders during the transition from pre-breeding to nest initiation, and through the subsequent eight months of paternal care. In doing so, we investigated the correlates of nest fate and clutch size, exploring hellbenders’ alignment with several endocrinological patterns observed in uniparental male fish. Understanding the endocrinology of hellbender paternal care is also vital from a conservation perspective because high rates of nest failure were recently identified as a factor causing population declines in this imperiled species. We corroborated previous findings demonstrating testosterone and dihydrotestosterone (DHT) to be the primary androgens in hellbender reproduction, and that cortisol circulates as the most abundant glucocorticoid. However, we were unable to identify a prolactin or a “prolactin-like” peptide in circulation prior to or during parental care. We observed ∼ 80 % declines in both primary androgens during the transition from pre-breeding to nest initiation, and again as paternal care progressed past its first month. In the days immediately following nest initiation, testosterone and DHT trended higher in successful individuals, but did not differ with males’ clutch size. We did not observe meaningful seasonality in baseline glucocorticoids associated with breeding or nesting. In contrast, stress-induced glucocorticoids were highest at pre-breeding and through the first two months of care, before declining during the latter-most periods of care as larvae approach emergence from the nest. Neither baseline nor stress-induced glucocorticoids varied significantly with either nest fate or clutch size. Both stress-induced cortisol and corticosterone were positively correlated with total length, a proxy for age in adult hellbenders. This is consistent with age-related patterns in some vertebrates, but the first such pattern observed in a wild amphibian population. Generally, we found that nesting hellbenders adhere to some but not all of the endocrinological patterns observed in uniparental male teleosts prior to and during parental care.

Nest survival of Crested Lark (Galerida cristata) in intensively used habitats in Central Poland

Breeding success of birds depends on survival during two critical stages of the reproductive period: First, egg laying and incubation, and then nestling and fledgling. This essential element of avian life history mirrors an evolutionary adaptation of parents to existing environmental conditions. The main factors that determine nest survival involve weather, predation and sibling competition. Despite numerous studies documenting their impact on breeding success, only a few have analysed the issue with regard to ground-nesting birds and estimated their survival functions. Therefore, we decided to examine nest survival probability of the Crested Lark (Galerida cristata) in a population that occupies newly established roadside habitats in Central Poland. The analysis is based on 141 nests monitored between 2018 and 2022. We found that the mean survival probability of the whole nesting period was 0.376, and it was higher during the egg stage (0.836) than during the nestling period (0.392). The Cox proportional hazards model shows that nest survival in the nestling stage is mainly affected by the time of breeding and the distance from the road edge, and also by mean temperature of the whole nesting period. In other words, the probability of a brood failure in the nestling stage decreases as the breeding season advances, whereas it increases among nests located closer to the road edge. Furthermore, during the whole nesting period, nest failure decreases as the temperature rises. Our study suggests that the Crested Lark, being a multi-brood and thermophilic species inhabiting temperate regions, may benefit more if its nesting attempts begin later during the season when breeding conditions become more favourable. However, we also take into consideration a hypothesis that nesting in grassy habitats near road edges may prove to be an ecological trap, attracting high densities of nesting birds but leading to their low nest success.

Flooding-induced failure of an invasive Burmese Python nest in southern Florida

Flooding-induced failure of an invasive Burmese Python nest in southern Florida

Invasive shrub species as nest substrates do not appear to impact nest failure for Yellow Warblers (Setophaga petechia)

Invasive shrub species as nest substrates do not appear to impact nest failure for Yellow Warblers (Setophaga petechia)

Small-scale land-use change effects on breeding success in a desert-living social bird

Abstract Human villages in deserts can provide resources in an otherwise stark environment, potentially buffering against extreme environmental conditions. It is thus expected that breeding within these villages would result in higher fitness. However, choosing to raise offspring in these resource-rich environments may have unintended negative consequences. Here, we studied the breeding success of a cooperative breeding bird nesting in habitats with different levels of human disturbance—the Arabian babbler (Argya squamiceps), in the Negev desert of Israel. We recorded 42 breeding attempts from 15 groups between March and July 2022. We examined overall breeding success, brood size, and causes of nest failure. When nestlings were 6 days old, we also calculated daily change in body mass and adult provisioning rate. We found that despite higher resource abundance in villages, proximity to villages did not affect provisioning rate, and nestlings gained less mass at higher temperatures for all nests. Currently, there is no evidence that human villages are providing oases of resources for nesting babblers. Further, various conservation interventions (e.g., encouraging residents to keep cats indoors) could improve babblers’ overall fitness. Ultimately, we highlight how, for some desert specialists, additional resources provided by humans may not do enough to counter potential negative effects.

High nest failure in a zebra finch population and persistent nest predation by a monitor lizard.

Predation is well known to have substantial effects on behaviour and fitness in many animals. In songbirds, nest predation is rarely observed directly, so that research focusses primarily on the consequences of predation and less on the behaviour of the predator. Here, we report predation data in a zebra finch (Taeniopygia catanosis) nest box population, highlighting a 22-min-long sequence, captured on video, of a sand goanna (Varanus gouldii) predating a zebra finch nest in the wild. This monitor lizard appeared to be extremely persistent with climbing and jumping up to the next box nine times, including three successive unsuccessful attempts that lead to a change in approach strategy. It removed all six nestlings from the nest box during those repeated approaches and consumed them. In combination with overall high predation rates in the study population we document here, the findings highlight the role that a single predator species can have on nest success and, thus potentially also breeding decisions and social organisation of the prey population. Specifically so in a species like the zebra finch which synchronises reproductive attempts through the use of social information acquired through nest inspections and which uses social hotspots where they could gather information on changes in local social composition due to the individualised signals they use.

Breeding performance and nest-site selection of Woodchat Shrikes Lanius senator near the southern edge of their breeding distribution

Numerous Woodchat Shrike (Lanius senator) populations, and Laniidae in general, are globally declining. A deeper understanding of their breeding ecology, including their nest-site selection and breeding performance, from hatching success to post-fledging survival, could contribute to their conservation. We studied breeding Woodchat Shrikes near the southern edge of their breeding range in Northern Israel, monitoring breeding pairs throughout the breeding season from March to July 2023 in three study areas at the slopes of the Golan Heights in a semi-open shrubland. We collected data on birds’ nesting success, including hatching and fledging success, as well as on breeding pairs’ productivity and post-fledging survival of Woodchat Shrikes. Furthermore, we gathered information on nest-site characteristics. In this part of their range, Woodchat Shrikes breed in relatively high densities, opportunistically selecting nest-sites within the area. Most pairs had at least two brood attempts and up to four were recorded. On average breeding pairs laid 4.63 eggs per brood, with a decreasing brood size later in the season. Breeding performance was not related to the nest-site characteristics with the exception of nest height above the ground, which had a positive influence on nesting success. The breeding performance of Woodchat Shrikes was relatively low compared to other studies, particularly when considering fledging success. Nest predation was likely a predominant cause for nest failures here; however, breeding pairs were able to substantially increase their breeding success with replacement broods. Compared to the low nesting success, the post-fledging survival was relatively high, indicating much higher predation pressure on nests compared to fledglings.

BREEDING BIOLOGY OF THE LOGGERHEAD SHRIKE LANIUS LUDOVICIANUS IN CENTRAL MEXICO

The Loggerhead Shrike Lanius ludovicianus has an exceptionally broad distribution in North America, with the southernmost populations found in central Mexico. The species has experienced severe declines throughout its range, and thus, is of conservation concern, particularly in USA and Canada. Life history data is scarce for Mexico, where both resident and migratory populations are found. In this study we provide information on the breeding biology of a population of Loggerhead Shrikes near the southern limit of its distribution in central Mexico. Based on data from 70 nests over three breeding seasons (2007–2009), we estimated the average nest density as 0.85 nests/ha with most nests built in mesquite trees Prosopis laevigata. Average clutch initiation date was March 28, with variation among years. The breeding period averaged 3.5 months, starting at the end of February, and extending to early June. The laying period averaged 4.6 days, incubation averaged 18 days, and the average brooding period 16.6 days, for a total average of 39.2 days from egg laying to the end of brooding. Clutch size averaged 4.1 eggs (range 2–5) with a mode of four eggs. The nesting success for the three years combined was 64.3% (range 54.5–68.9%). Daily survival rate was estimated to be 0.749 using logistic exposure. The average number of fledglings at successful nests was 1.5. Predation was the main cause of nest failure, accounting for 35.7% of all active nests. In general, life history traits of this Mexican Loggerhead Shrike population are like those reported for breeding populations in more northern parts of its range; however, clutch size was smaller and average incubation period was significantly longer, probably because of latitudinally-related environmental factors.

Free‐ranging livestock reduces the habitat suitability of subalpine pheasants during breeding season in Southwest China

AbstractFree‐ranging livestock pose a threat to forest biodiversity, exerting a profound influence on the survival of several endangered species. The mountains of Southwest China represent a biodiversity hotspot enriched with pheasant species of global significance; however, the influence of free‐ranging livestock on the survival and population of forest pheasants remains unclear. We examined the impact of livestock on the habitat suitability of subalpine pheasants and the associated mechanism during the breeding season in Southwest China (forest with and without grazing) over 2 years (2018–2019). Artificial nest experiments monitored by infrared‐triggered cameras showed that the nest failure rate was 2.18 folds higher in livestock‐active areas, where livestock directly accounted for 26.09% of all nest predation events, compared with other areas. Small animal trapping and vegetation quadrat surveys showed a 46% lower abundance of ground invertebrates, a critical food resource for breeding pheasants and their chicks, in grazing areas than in grazing‐free areas. Thus, livestock grazing markedly reduces the habitat suitability of subalpine pheasants during the breeding season. These results highlight the impacts of grazing on endangered pheasant species and the underlying mechanisms, necessitating centralized livestock management in these protected areas from April to July, coupled with livelihood transformation initiatives.

Assessing Southern Gulf of Mexico Resilience: Least Tern Nesting Failure During the COVID-19 Pandemic

The COVID-19 lockdown opened an opportunity to assess the response of animal populations to diminished human activities. As coastal dunes face many disturbances caused by increasing human activities, we assessed the effect of reduced human mobility on coastal bird diversity and abundance and on the Least Tern nest failure rate on an island in the southern Gulf of Mexico before, during, and after the lockdown to test the hypothesis that diminished tourism and recreational activities can contribute to the conservation of coastal ecosystems by increasing species richness and abundance and decreasing the nest failure rate. We used data from 2016 to 2021 to estimate nesting failure probabilities using Bernard’s cumulative distribution function, Kaplan‒Meier tests, and Cox regression for hazard rates. Bird species richness and abundance were compared using Kruskal‒Wallis rank tests. Factors related to breeding site preference were assessed using the BIOENV method. The lockdown did not affect species richness, but bird abundance was inversely related to pedestrian traffic (rho = − 0.908, p < 0.0001, n = 48). Nest failure decreased during the lockdown in 2020 (p < 0.0001) due to reduced presence of people, which allowed occupancy of sites never used before. During the lockdown, the proportion of nest failure was lower than that in the other sampling years (p < 0.0001, φ range = − 0.445 to − 0.278). Accordingly, diminished pedestrian traffic can increase nest survival (log-rank p < 0.0001). Policies to reduce beach pedestrian traffic will help strengthen wildlife conservation and building coastal resilience.

Saffron-cowled Blackbirds’ reduced nest success in Argentina’s agricultural land highlights the importance of non-agricultural habitat for its conservation

Abstract The Saffron-cowled Blackbird (Xanthopsar flavus) is a globally endangered icterid endemic to the southern South American grasslands. Temperate grasslands are among the most threatened ecosystems in South America due to their high rate of land use change. In northeastern Argentina, over the last century, the conversion of natural grasslands to livestock farming, croplands, and afforestation has resulted in significant losses of breeding habitat for the Saffron-cowled Blackbird. Consequently, it has suffered severe populational declines, and its remaining populations are fragmented. In order to understand the impact of agricultural systems on the Saffron-cowled Blackbird populations, we studied its breeding biology (clutch size, hatching success, nestling production, and fledgling success) and the main parameters that influence nest survival rate in five breeding habitat types. During the breeding seasons of 2015 to 2019, we located nests and monitored their fate. We found that the cumulative probability of nest survival over the entire nesting cycle (i.e. laying, incubation, and chick rearing) was 0.06, and was lower for nests situated in grazed land covers. Conversely, nest survival was greater in breeding sites without agricultural use, particularly in marshes. Predation was the main cause of nest failure (76%), followed by brood parasitism (10%), and trampling by cattle and agricultural machinery (6%). Brood parasitism rates were higher in grazed paddocks, contributing together with predation to the failure of nests in this habitat. Our findings indicate a negative impact of livestock ranching on Saffron-cowled Blackbird reproduction. Non-agriculture habitats, such as wetlands and flooded areas, are important as refuges for nesting. Thus, the creation of breeding refuges (non-productive sites) within agricultural matrices, in association with biodiversity-friendly agricultural practices, is crucial to ensure the Saffron-cowled Blackbird’s maintenance.

Concurrent threats and extinction risk in a long-lived, highly fecund vertebrate with parental care.

Detecting declines and quantifying extinction risk of long-lived, highly fecund vertebrates, including fishes, reptiles, and amphibians, can be challenging. In addition to the false notion that large clutches always buffer against population declines, the imperiled status of long-lived species can often be masked by extinction debt, wherein adults persist on the landscape for several years after populations cease to be viable. Here we develop a demographic model for the eastern hellbender (Cryptobranchus alleganiensis), an imperiled aquatic salamander with paternal care. We examined the individual and interactive effects of three of the leading threats hypothesized to contribute to the species' demise: habitat loss due to siltation, high rates of nest failure, and excess adult mortality caused by fishing and harvest. We parameterized the model using data on their life history and reproductive ecology to model the fates of individual nests and address multiple sources of density-dependent mortality under both deterministic and stochastic environmental conditions. Our model suggests that high rates of nest failure observed in the field are sufficient to drive hellbender populations toward a geriatric age distribution and eventually to localized extinction but that this process takes decades. Moreover, the combination of limited nest site availability due to siltation, nest failure, and stochastic adult mortality can interact to increase the likelihood and pace of extinction, which was particularly evident under stochastic scenarios. Density dependence in larval survival and recruitment can severely hamper a population's ability to recover from declines. Our model helps to identify tipping points beyond which extinction becomes certain and management interventions become necessary. Our approach can be generalized to understand the interactive effects of various threats to the extinction risk of other long-lived vertebrates. As we face unprecedented rates of environmental change, holistic approaches incorporating multiple concurrent threats and their impacts on different aspects of life history will be necessary to proactively conserve long-lived species.

Demographic response of osprey within the lower Chesapeake Bay to fluctuations in menhaden stock

Forage fish support the largest fisheries in the world and play a vital role in marine food webs by transferring energy from plankton to consumers within higher trophic levels. Growing commercial demand for these species and concern for the impact of over harvest on predator populations has driven a paradigm shift in management objectives from maximizing economic return to the establishment of ecosystem-based limits on harvest rates. How well current harvest policy supports noncommercial species like piscivorous birds remains poorly understood. We investigated the relationship between osprey breeding performance within the lower Chesapeake Bay and a menhaden stock index during a period (1974-2021) when the menhaden index fluctuated over 35-fold. Reproductive rate (young/pair/year), brood provisioning (fish/10-h) and the proportion of menhaden in the diet all declined during the study period. Indicators of food stress including brood reduction and nest failure increased during the study period. The population transitioned from reproductive surplus (demographic source) to reproductive deficit (demographic sink). A significant relationship between reproductive rate and the menhaden index suggests that osprey population viability requires that the menhaden stock be restored to 1980s levels. Current ecological reference points based on the food requirements of predatory fish are unlikely to protect the osprey population. We suggest the establishment of menhaden or reproductive thresholds designed to allow osprey to meet demographic targets (1.15 young/pair/year).

The effect of Common Cuckoo parasitism on the annual productivity of a host population

Avian interspecific brood parasitism is an excellent system for studying coevolutionary processes in nature because brood parasites directly affect host reproductive success. Most research on avian brood parasitism has, therefore, focused primarily on specific host anti-parasite behaviours and parasite counter-adaptations. However, the population-level consequences of brood parasitism for host species are poorly understood. This study investigated the effect of Common Cuckoo (Cuculus canorus) parasitism on the productivity of a local population of the Great Reed Warbler (Acrocephalus arundinaceus) host in south-western Slovakia. A total of 495 females nesting at the studied site successfully fledged 1321 of their own young and 63 young of the Common Cuckoo over the course of 15 years (2008–2022), and the annual rate of successful parasitism ranged from 18% to 44% over this period. As predicted, higher rates of successful cuckoo parasitism significantly reduced the annual productivity of the local Great Reed Warbler population, and its contribution to decreased host reproductive success was at about the same rate as overall nest failure caused by predation and other environmental factors. Such a heavily parasitized population was probably maintained by immigrants from other populations and density-dependent selection, which is also consistent with source–sink dynamics. However, further long-term studies monitoring parasitized populations are required to confirm these findings.

Monitoring wader breeding productivity

A robust understanding of the mechanisms driving demographic change in wild animal populations is fundamental to the delivery of effective conservation interventions. Demographic change can be driven by variation in adult survival, recruitment of juveniles into the breeding population or breeding productivity – the number of fledglings produced per breeding pair. Across Europe, low breeding productivity in wader populations has been a significant driver of population decline, increasing the importance of gathering accurate data on breeding productivity. Monitoring wader breeding productivity is challenging because finding nests can be time‐consuming and requires experienced fieldworkers; wader chicks are nidifugous and difficult to count due to their cryptic behaviour; and waders often have high re‐laying rates following nest failure, meaning that hatching or fledging can be highly asynchronous. This paper reviews approaches to estimating breeding productivity where fieldworkers either record the agitation or alarm‐calling behaviour of adults with dependent young, make direct observations of broods on survey visits, or both. Using a systematic literature search (restricted to Europe where most of these studies have taken place) we identified 38 peer‐reviewed papers which used this approach. The productivity metrics produced can be divided into the following categories: (i) ‘Hatching Success’ (HS), (ii) ‘Fledging Success’ (FS) and (iii) ‘Young Fledged Per Pair’ (YFP), from the coarsest to the most precise. The first two metrics are most often used when direct observations of broods are not possible due to the behaviour of broods or vegetation structure; YFP is preferred if brood counts are possible. Design of an appropriate metric depends on (i) whether accurate brood counts are possible; (ii) whether adults exhibit diagnostic agitation behaviour when young are present; (iii) whether individual breeding territories are separable; (iv) whether re‐nesting rates are assumed to be high; and (v) the availability of experienced surveyors (particularly where behavioural observations are required). Globally there are many wader species for which the methods described here could provide valuable information and we hope this review encourages further development or adoption of these methods.