A new study finds that the world’s seabird populations have plummeted by almost 70% in just 60 years. 
 
 Every day for sixty million years, seabirds have performed mind-boggling acts of derring-do: circumnavigating the globe without rest, diving more than 200 meters in treacherous seas for a bite of lunch, braving the most unpredictable weather on the planet as if it were just another Tuesday and finding their way home in waters with few, if any, landmarks. 
 
 
 
 But now seabirds, like so many other species, may have met their match. 
 
 Conservationists have long known that many seabird populations are in decline, but a recent paper in PLOS ONE finds the situation worse than anticipated. According to the researchers, seabird abundance has dropped 69.7% in just 60 years – representing the deaths of some 230 million animals. 
 
 “I was very surprised with the result, it was considerably greater than I’d expected,” said Edd Hammill, co-author of the paper, with Utah State University. “What we should take away from this is that something is serious amiss in the oceans.” 
 
 Facebook Twitter Pinterest The Brown Booby (Sula leucogaster) is listed as Least Concern and is found throughout the pantropical oceans. However some populations are suspected to be in decline owing to disturbance and unsustainable levels of exploitation. Photograph: Ben Lascelles/Birdlife International 
 
 Ben Lascelles, a Senior Marine Officer with Birdlife International, who was not involved in the study, said he found the research alarming because the decline appeared practically indiscriminate, hitting a “large number of species across a number of families.” 
 
 
 
 Seabirds, which include any bird that depends largely on the marine environment, comprise nearly 350 species worldwide – an astonishing variety of extreme-loving birds. For example, the indefatigable wandering albatross, which sports the largest wingspan on the planet; the child-sized Emperor penguin, the only bird that breeds during the Antarctic winter; and the tiny storm petrel that practically capers on the water as it feeds – they are named for St. Peter after all. 
 
 But, given that seabirds inhabit both the open ocean and the shoreline, this eclectic mix of birds faces a litany of threats: overfishing, drowning in fishing lines or nets, plastic pollution, invasive species like rats in nesting areas, oil and gas development and toxic pollution moving up the food chain. And as if these weren’t enough, the double-whammy of climate change and ocean acidification threatens to flood nesting sites and disrupt food sources. 
 
 “Seabirds are particularly good indicators of the health of marine ecosystems,” explained lead author, Michelle Paleczny with the University of British Columbia and the Sea Around Us Project. “When we see this magnitude of seabird decline, we can see there is something wrong with marine ecosystems. It gives us an idea of the overall impact we’re having.” 
 
 Bu with such a large number of species across such a wide variety of environment one is left asking: how did the scientists count so many birds? 
 
 Counting Birds 
 
 First, the team of researchers scoured all the population data on seabirds available. They found demographic data on 3,213 populations. But they couldn’t use all of theses counts, since conservationists had surveyed many of these far-flung populations just once or twice – not enough to show a real trend 
 
 
 
 The team eventually selected 513 populations that had been counted at least five times. In all, these populations represented about 19 percent of the world’s seabirds. 
 
 Still, Hammil said he believes the team’s findings “are an accurate representation of what is happening worldwide.” 
 
 He added, “although we did not include every population, all seabird families were included, and we included populations from every major coastline in the world.” 
 
 
 
 Paleczny also said that when the researchers looked at the differences between monitored and unmonitored populations, they saw “no evidence that the monitored populations are declining more.” 
 
 Facebook Twitter Pinterest The Near Threatened Black-footed Albatross (Phoebastria nigripes) is a species at risk of accidental bycatch in fisheries of the North Pacific. However, simple mitigation measures have proved to be very effective at keeping seabirds off the hooks. Photograph: Ben Lascelles/Birdlife International 
 
 The findings are also bolstered by past research. In 2012 a paper in Bird Conservation International found that 28 percent of seabird species are threatened with extinction with 47 percent in decline. This meant, in all, seabirds were about twice as likely as land-based birds to be threatened with extinction. 
 
 “The trends for many seabird species have clearly been downwards for a number of years, and this paper provides further evidence of this,” Lascelles said. 
 
 Still, Paleczny and Hammil’s research arguably paints an even more alarming picture of the state of the world’s seabirds. For example, according to them, the tern family has fallen by 85%, frigatebirds by 81%, petrels and shearwaters by 79%, and albatrosses by 69%. 
 
 
 
 Such dismal findings point to one of the study’s patterns: open ocean birds – such as albatrosses, frigatebirds, petrels and shearwaters – are generally faring worse than birds that stick near the coasts. 
 
 “[Open-ocean] seabirds are hit especially hard due to their large geographic ranges. Because these species travel so far, there is a greater chance they will encounter threats,” said Hammill who noted that coastal birds “in some cases” are doing better because of improved management of breeding areas and improved fishing gear. 
 
 But even when threats were minimised, Lascelles noted that recovery requires diligence and patience. 
 
 Facebook Twitter Pinterest A gannet grabs a fish by its beak, 2014, in Shetland, Scotland. Gannets, and other seabirds, depend on abundant fish populations to survive. Photograph: Richard Shucksmith/BarcroftMedia 
 
 “Most seabirds are long-lived and slow reproducing, this means even quite small increases in mortality can lead to significant population declines, which they take a long time to recover from.” 
 
 And even some widely-dispersed coastal birds are undergoing heavy declines. For example, the study found that cormorant and shag populations have fallen by 73%. 
 
 Going Forward 
 
 Given all the threats facing the world’s seabirds, it’s fair to ask: where do we start when it comes to conservation? 
 
 
 
 “We already have solutions to many of the threats...it’s just they need scaling up and implementing across industries and geographies,” Lascelles said. “Increased efforts should be made to rid seabird colonies of invasive species, reduce bycatch in fisheries or the ensnaring of birds in fish nets, and setting up conservation areas.” 
 
 Facebook Twitter Pinterest Laysan Albatross adult and chick on nest dwarfed by pile of marine debris collected on Midway Atoll coast by volunteers. Plastic poses a major threat to the world’s seabirds and other marine species. The Laysan Albatross is categorised as Near Threatened by the IUCN Red List. Photograph: Alamy 
 
 Paleczny also called for the creation of international marine protected areas to cover the wide ranges of seabirds. 
 
 Protected areas in the oceans lag far behind those on land. Currently, only 2% of the world’s oceans are under some form of protection and less than half of those ban fishing altogether. In contrast, nearly 15% of the world’s terrestrial landscape is protected. 
 
 With so little of the ocean theoretically closed to fisheries – less than 1% – it’s hardly shocking that many seabirds are suffering from overfishing. Indeed, an illuminating study from 2012 found that whenever fish abundance dropped below one-third of maximum levels, seabird populations began to fall in response. 
 
 “What this is saying is that [seabirds] have evolved to exploit average to above-average feeding conditions,” co-author Ian Boyd told Mongabay in 2012. “This isn’t really very surprising, but some things don’t become obvious until the evidence is right in front of you.” 
 
 At the time, Boyd said their findings should result in a new campaign to save “one third for the birds” (and other marine predators) from the world’s fisheries. 
 
 But to Hammill the “most pressing issue” is plastic pollution. 
 
 Long neglected by environmentalists – perhaps due to the intractability of the problem – the issue of plastic pollution in the oceans has been slowly getting more notice. A paper released last month found that 90% of the world’s seabirds likely have plastic in their stomachs. 
 
 “I have seen everything from cigarette lighters...to bottle caps to model cars. I’ve found toys [inside seabird guts],” co-author Denise Hardesty, with CSIRO, told the Associated Press. 
 
 
 
 Up to 90% of seabirds have plastic in their guts, study finds Read more 
 
 Seabirds continually mistake plastic for fish eggs, devouring large amounts. Plastic in animals’ stomachs not only release deadly toxins, but can also lead to slow starvation by obstructing the animals’ bowels. Birds even feed plastic bits to their young, killing their fledglings en masse. 
 
 In the end, large-scale actions to help seabirds could also go a long way in cleaning-up our increasingly trashed marine ecosystems. 
 
 “The oceans are still woefully under protected and fisheries need greater management and enforcement. All of these activities need investment and support of governments around the world to make them happen,” Lascelles said. “These actions will build resilience in the seabird populations in the short term, which they need in the face of emerging threats such as climate change.” 
 
 
 
 Facebook Twitter Pinterest No other bird breeds further south than the Near Threatened Adelie Penguin (Pygoscelis adeliae). Numbers are increasing in the Ross Sea region and decreasing in the Peninsula region, with the net global population increasing overall. But other penguin species aren’t faring so well. Photograph: Ben Lascelles/Birdlife International 
 
 Facebook Twitter Pinterest The accidental bycatch of huge numbers of seabirds in a variety of fisheries (e.g. longline, trawl, gillnets) is one of the main threat facing seabirds and has driven the declines in many species, particularly albatross. However a number of simple mitigation measures are available, and where they have been implemented the reduction in bycatch has been dramatic. Photograph: Ben Lascelles/Birdlife International ||||| Consider the albatross. 
 
 A bird that mates for life and flies over 6,000 miles for food, the albatross has seen profound population declines over the past several decades. It appears now as though a harbinger for its own demise. 
 
 Or take the Fiji petrel, a black, tube-nosed bird that spends almost its entire life skimming the oceans. The petrel, the albatross and other birds suffer when the oceans are polluted and overfished and a new study in PLOS One suggests they are paying a heavy price. Since the 1950s, the study concludes that seabird numbers have dropped by nearly 70 percent. 
 
 "Seabirds are particularly good indicators of the health of marine ecosystems," said University of British Columbia's Michelle Paleczny, a co-author of the study and a researcher with the Sea Around Us project. "When we see this magnitude of seabird decline, we can see there is something wrong with marine ecosystems. It gives us an idea of the overall impact we're having." 
 
 Daniel Donnecke 
 
 For the study, the researchers compiled information on more than 500 seabird populations from around the world, representing 19 percent of the global seabird population. They found overall populations had declined by 69.6 percent or the equivalent to a loss of about 230 million birds in 60 years. 
 
 Some of worst drops were in the Southern Hemisphere, which includes Australia, Antarctica, most of South America and a third of Africa. Among the families hardest hit have been Sternidea, which includes terns and saw declines of 85.8 percent. That was followed by Frigatidae, a family which includes frigatebirds and saw declines of 81.7 percent. Then there was Procellariidae, a family that includes petrels and saw declines of 79.6 percent and Phalacrocoracida, a group that includes cormorants and shags, saw drops of 73.6 percent. 
 
 The family of Diomedeidae, which includes albatross, saw declines of 69 percent. 
 
 "We are seeing a serious and worrying decline," said Rory Crawford, a senior policy officer with BirdLife International's marine Programme, which in 2012 estimated that nearly half of seabird populations were in trouble. 
 
 Daniel Donnecke 
 
 "It's a large number of species across a number of families that are in decline and that is alarming," he said. "This is not about going to one location. It's about a broad range of threats effecting sea birds." 
 
 The study concluded that the dramatic declines were caused by a range of factors, including overfishing of the fish seabirds rely on for food. Hundreds of thousands of birds each year get tangled in fishing gear and die or are sickened by oil spills or plastic pollution. They also face threats to their colonies from invasive predators such as rats that feast on their eggs. Other factors include destruction and changes to seabird habitat as well as the environmental and ecological changes caused by climate change. 
 
 They are especially vulnerable because of their dependence of a wide swath of open water for food, traveling the world's oceans to forage for food and returning to the same colonies to breed. 
 
 George Wallace, vice president for oceans and islands at the American Bird Conservancy, said the impacts especially on long-distance fliers like the petrels and shearwaters shows just how much "humans have altered the planet." 
 
 Sea Around Us 
 
 "They may be responding to oceanic conditions that are thousands of miles from their breeding colonies," he said. "If you are a Hawaiian petrel that undertakes a foraging flight that literally takes up most of the northern Pacific Ocean and you don't find food, that is a tremendous exertion of energy and a chick that won't be fed." 
 
 A big part of the problem, Paleczny said, was the absence of efforts to protect many of these birds. 
 
 "Our work demonstrates the strong need for increased seabird conservation effort internationally," Paleczny said. "Loss of seabirds causes a variety of impacts in coastal and marine ecosystems." 
 
 Crawford agreed, saying increased efforts should be made to rid seabird colonies of invasive species, reduce bycatch, or the ensnaring of birds in fish nets, and setting up conservation areas for all aspects of the birds' life cycles from breeding sites to migratory routes. 
 
 "There are things we can do. What we need is investment and support of governments around the world to make this happen," Crawford said. "These actions will build resilience in the seabird populations in the short term, which they need in the face of climate change." 
 
 In a sign of hope, some bird populations have increased their numbers. A group called Hydrobatidae, which includes storm petrels, saw its numbers rise more than 45 percent while the family of Alcidae, which includes puffins and murres, climbed 9.1 percent. 
 
 The researchers didn't explain why some groups appeared to be thriving or whether this reflected all species within the groups, although it could be attributed to successful efforts to rid several Pacific islands of cats, rats and other invasive species. 
 
 And in another conservation success, Birdlife recently worked with fishermen in South Africa to reduce bycatch by 99 percent and thus give a boost to the albatross. 
 
 "What I'm encouraged about is that we know what the solutions are," Crawford said. "We know the seabirds will respond spectacularly well if we remove invasive species from their breeding colonies. We know that we can reduce seabird bycatch in fisheries with simply measures that are not costly and don't affect the efficiencies of the fishery operation." ||||| Seabird population changes are good indicators of long-term and large-scale change in marine ecosystems, and important because of their many impacts on marine ecosystems. We assessed the population trend of the world’s monitored seabirds (1950–2010) by compiling a global database of seabird population size records and applying multivariate autoregressive state-space (MARSS) modeling to estimate the overall population trend of the portion of the population with sufficient data (i.e., at least five records). This monitored population represented approximately 19% of the global seabird population. We found the monitored portion of the global seabird population to have declined overall by 69.7% between 1950 and 2010. This declining trend may reflect the global seabird population trend, given the large and apparently representative sample. Furthermore, the largest declines were observed in families containing wide-ranging pelagic species, suggesting that pan-global populations may be more at risk than shorter-ranging coastal populations. 
 
 Despite the global importance of seabirds, both to marine ecosystems and as indicators of marine ecosystem status, analysis of their population trends is typically limited to the relatively small spatial and temporal scales at which data are collected. The only global assessment of seabird population status, based on extinction risk as assessed by the IUCN Red List of Threatened Species, indicates that one third of seabird species are threatened with extinction, one half are known or suspected to be in decline, and at least four species are extinct [ 12 ]. 
 
 Seabird population changes are good indicators of long-term and large-scale change in marine ecosystems because seabird populations are relatively well-monitored, their ecology allows them to integrate long-term and large-scale signals (they are long-lived, wide-ranging and forage at high trophic levels) [ 10 – 11 ], and their populations are strongly influenced by threats to marine and coastal ecosystems. These threats include entanglement in fishing gear, overfishing of food sources, climate change, pollution, disturbance, direct exploitation, development, energy production, and introduced species (predators such as rats and cats introduced to breeding islands that were historically free of land-based predators) [ 12 ]. Knowledge of changes in seabird populations is also inherently important because seabirds play important roles in island and marine ecosystem processes, function and resilience, by acting as predators, scavengers, cross-ecosystem nutrient subsidizers, and ecosystem engineers [ 2 , 13 – 16 ]. 
 
 In order for the trend estimated for the monitored population to be representative of the global population, the monitored sub-sample would have to be representative of the global population, so we would expect the taxonomic diversity and spatial distribution of the monitored populations to be diverse and reflective of the overall global population. To assess this, we compared the monitored populations (i.e., those 513 populations with >4 records) and the unmonitored populations (i.e., those 2696 populations with 1–4 records) the diversity and representativeness of taxa, marine regions, declining populations, and missing populations (i.e., populations with no records). 
 
 In the Eqs 1 and 2 , x is a m*T matrix representing the state of the random variable X t at each time t. The parameter w is a m*T matrix of the process errors at time t, with a mean 0 and covariance matrix Q t . Parameter y represents a n*T matrix of the observation, some of which may be missing. v is a n*T column vector of the non-process errors, the observation errors at t and multivariate and normal with mean 0, and covariance matrix R t . u and a are parameters. As each of the seabird populations was reproductively and often geographically isolated, we assumed they had independent random errors (diagonal Q matrix) and had different population parameters (u and a). As the population census data were collected by different groups utilizing different techniques (even within the same population), and some species are easier to detect than others, we stipulated independent observation variances for each population (diagonal and unequal R matrix). However, much of the variation in process error may be the result of environmental, rather than demographic stochasticity, meaning that populations may show similar trends and the assumption of independent process error is invalid. We therefore tested the assumptions of independence by running subsequent versions of the MARSS model where process and measurement errors were set as equal for each population. We used maximum likelihood with an Expectation-Maximum algorithm to estimate population trends as an auto-regressive stochastic process for all populations that had at least five records in their time-series (a prerequisite). These 513 of the total 3213 populations ( S1 Table ) are hereafter referred to as the monitored portion of the global seabird population. MARSS models provide an estimate of the population size in the years when no survey was conducted. Using this technique we were then able to obtain population estimates for all of the 513 monitored populations between the years 1950–2010. To represent the overall trajectory of monitored seabird populations, we summed the estimated number of seabirds, and their standard errors across all populations for each year, and plotted the trajectory. To understand how the fixed parameters (u and a) contributed to the population trajectory compared to the random variances (Q and R), we calculated the size of Q and R as a proportion of u and a. 
 
 We obtained data from primary sources including journal articles, books, and unpublished reports. We obtained population sizes as breeding pairs or total population; for comparison between the two, we converted records reported in breeding pairs to total population assuming that the population includes 30% non-breeders, a commonly assumed estimate for global seabird studies [ 18 – 20 ]. If a population size was reported as a range (e.g., 100–200 breeding pairs), we assumed the population size to be the geometric mean of the minimum and maximum records; the geometric mean is the square root of the product of a pair of values, and is applied in ecology to approximate central tendency [ 21 ]. For an example of the population database contents, see S3 Table . The database derived from our study is maintained by the Sea Around Us Project and will be made publicly available at www.seaaroundus.org . 
 
 The monitored population, in comparison with the unmonitored population, contained a slightly higher percentage of declining populations, but also a higher percentage of increasing populations. Based on available data and methods described above, overall decline was detected in 38% of the monitored populations and 27% of the unmonitored populations, increase was detected in 61% of monitored populations and 29% of unmonitored populations, and no change was detected in 1% of monitored populations and 44% of unmonitored populations (the latter is due to the high number of populations with only one population record). Threatened species (i.e., status of Vulnerable, Endangered or Critically Endangered on the International Union for Conservation of Nature (IUCN) Red List) comprised 26% of monitored species; this percentage is slightly lower than that across all of the world’s species (i.e., 28%) [ 12 ]. 
 
 The taxonomic diversity of the monitored population was high, but not reflective of the taxonomic composition of the global seabird population. Half of all seabird species (i.e., 162 of 324) were represented in the monitored portion of the population ( S1 Table ). The extent to which each species was monitored varied; 17% of monitored species had 100% of their populations monitored, and 43% of species had at least 50% of their populations monitored. Thirteen families (i.e., all except Pelecanoididae) were represented in the monitored portion of the global seabird population ( Fig 3 ). The extent to which each family was monitored varied from 1–5% (Hydrobatidae, Fregatidae, Phaethontidae, Stercorariidae), 12–20% (Procellariidae, Sternidae, Alcidae), 34–44% (Laridae, Sulidae), 54–59% (Phalacrocoracidae, Pelecanidae, Spheniscidae), and 89% (Diomedeidae). Of the seven numerically abundant seabird families that together account for approximately 97% of the global seabird population (Procellariidae, Alcidae, Sternidae, Spheniscidae, Pelecanoididae, Hydrobatidae, Laridae), two were poorly represented (Pelecanoididae and Hydrobatidae, jointly accounting for <1% of the monitored population) while the remaining five families were relatively well represented (jointly accounting for 92% of the monitored population). We found considerable differences in the population trajectories of different families over time. Of the monitored populations, we found overall increases in Alcidae (9.1%), Hydrobatidae (45.4%), and Sulidae (1.1%), and decreases in Diomedeidae (69.0%) Frigatidae (81.7%), Pelecanidae (35.3%), Laridae (17.4%), Phaethontidae (25.8%), Phalacrocoracidae (73.6%), Procellariidae (79.6%), Spheniscidae (32.3%), Stercorariidae (65.4%), Sternidae (85.8%). 
 
 When Q and R matrices were set as diagonal and unequal (independent process and non-process errors used for each population), MARSS modeling revealed a substantial decline in seabird populations throughout the modern industrial era. This decline represented a 69.7% loss between 1950 and 2010, in the monitored portion of the global seabird population ( Fig 2 ). The overall value of u across all populations was -8868.25, implying that on average, each seabird population lost a considerable number of individuals per year. A substantial proportion of this loss was due to large declines in the five most abundant populations, all located in the southern hemisphere. Between them, the populations of Sooty Terns (Sternidae) from French Polynesia and South Orkney, the South Sandwich Island populations of both Soft-plumaged Petrels and Kerguelen Petrels (both Procellariidae), and the Peruvian population of Guanay Cormorants (Phalacrocoracidae) accounted for over 30% of the total numbers of seabirds in the sampled population in 1950; all of these populations were reduced to less than 5% of their initial size by 2010. 
 
 Discussion 
 
 Drivers of a declining trend in the monitored portion of the global seabird population The cause of the estimated overall decline in seabird populations is likely a suite of threatening human activities—introduced species at nesting colonies (e.g., rats, cats), entanglement in fishing gear at sea, overfishing of food sources by humans, climate change and severe weather, pollution, disturbance, direct exploitation (harvesting chicks, eggs, adults), development, and energy production [12]. Some of these threats affect most species across the globe (e.g., climate change is a global process, although some regions will be more detrimentally affected), while others will be more local processes, or impact species disproportionately based on their ecology and/or life-history attributes (e.g., overfishing of food sources has a strong negative impact on seabirds with small body size, specialized diets, energetically expensive foraging, and surface foraging [23]). The impacts of some threats pre-date our seabird population data [24–27] and therefore a potentially large percentage of seabird populations were already suppressed prior to our 1950 baseline. Additionally, exploitation of other marine taxa (e.g., whales, sea otters, fish) has contributed indirectly to changes in seabird populations by altering the quantity, quality and spatial distribution of their prey [28]. While seabird conservation efforts have been successful in reducing mortality of some species in recent decades, for example, banning some direct exploitation [27], eradicating some introduced predators [29], reducing some entanglement in fishing gear [30], these efforts are evidently not sufficient in terms of stopping or reversing large-scale seabird decline, especially as new threats emerge, notably industrial harvesting to food [31]. Throughout the 1950–2010 timeframe of our study, overall threat rates have likely increased alongside growth in human population and industrialization although there may be annual variation in threats and threat response. Relatively low variation was observed in the rate of decline of the monitored population of seabirds throughout the timeframe (Fig 2), perhaps due to the continuous growth and expansion of threats and/or the lack of temporal resolution in available data. Climate oscillations can contribute to patterns in seabird abundance by affecting prey availability [32], although they are not likely the driving cause of the observed decline, as the continuous decline of seabirds over the timeframe of this study does not mirror any known climate oscillations. The interaction of climate cycles with threatening human activities may however be at play; in both Peru and California, depletion of seabird prey by fisheries has contributed to decreased resilience of seabirds to natural climate cycles, resulting in declines under poor climatic conditions and lack of natural rebound under good climatic conditions [33–34]. 
 
 Global significance of the estimated trend in the monitored portion of the global population Although the monitored portion of the world’s seabirds represents a subsample of the global seabird population, and we therefore cannot be certain the decline we have uncovered represents the pattern for the global seabird population, our relatively large sample suggests that a substantial global decline has occurred. Our findings also correspond with the highly threatened status of many of the world’s seabird species [12]. Investigation of how well our subsample represents the global population revealed no strong bias towards particular taxa, marine regions or declining populations. Half of all seabird species were represented and thirteen of fourteen families were represented. While families were not sampled in proportion to their numerical abundance, there was no apparent bias in sampling related to the proportion of threatened species per family [12]. For example, particularly well-represented families (in absolute and relative terms) include both families containing relatively high percentages of threatened species (Spheniscidae, Procellariidae, Diomedeidae) and relatively low percentages of threatened species (Alcidae, Laridae), while two families with particularly high percentages of threatened species are poorly represented (Hydrobatidae, Pelecanoididae) [12]. Sampling effort was not even across marine regions, but there was no apparent relationship between sampling effort and overall threat intensity across marine regions; of the regions with strongest threatening human activities, some were relatively well-monitored (northeast Atlantic) while others were relatively poorly monitored (Asia) [1]. While the monitored portion in comparison with the unmonitored portion of the global population contained a slightly higher percentage of declining populations, it also contained a much higher percentage of increasing populations (because the unmonitored population had a high number of populations with only one record), and a slightly lower representation of threatened species. A seabird global population estimate derived from our data was similar to an existing global estimate, suggesting that only a small minority of the global seabird population lacks some degree of population monitoring during the timeframe of the study. Overall, the lack of bias observed in the taxa, marine regions, and declining populations in the subsample, in addition to indication that most of the world’s population has been sampled at least once, suggests that the trend observed for the monitored portion of the population may reflect an overall trend in the global seabird population.
– There are nearly 350 species of seabirds roaming the planet, ranging from the wandering albatross (with the world's largest wingspan) and the child-size emperor penguin (the only bird to breed in Antarctic winters) to tiny storm petrels that dance on the water as they eat, reports the Guardian. But a study in PLoS ONE recently found that the much-talked-about decline in seabird populations is far worse than previously thought—with 69.7% of the flock, which has soared the globe for 60 million years, disappearing over the course of just 60 years, representing the loss of some 230 million animals. "I was very surprised with the result, it was considerably greater than I’d expected," co-author Edd Hammill says. "What we should take away from this is that something is seriously amiss in the oceans." Seabirds are battling more than the huge double whammy of climate change and ocean acidification that wreak havoc on food sources and nesting sites; they're also threatened by plastic pollution, overfishing and fish nets, oil and gas development, and invasive species in nesting areas. For their calculations, researchers used data on more than 500 seabird populations that represent 19% of the global seabird population and included all seabird families from every major coastline in the world. "This is not about going to one location," one expert tells CBS News. "It's about a broad range of threats affecting sea birds." Plastic pollution is, to Hammill, "the most pressing issue," with birds eating large amounts, being poisoned, and having bowel obstructions. But there are some successes, including the group BirdLife working with fishermen in South Africa to reduce bycatch by 99%. (Marine life in general is faring nearly as badly.)