Plastic poses biggest threat to seabirds in New Zealand waters, where more breed than elsewhere
Plastic pollution has the potential to cause the worst damage to seabirds in the seas around Aotearoa New Zealand, where many of them come to feed and breed.
Aotearoa boasts the greatest diversity of seabirds in the world. Of the 360 global seabird species, 86 breed here and 37 are endemic, which means they breed nowhere else.
Some 90% of New Zealand’s seabirds are threatened with extinction. They (and many other marine species) are under pressure from pollution, climate change, and overexploitation of marine resources. Plastic pollution could be the final nail in the coffin for many seabirds that are already struggling for survival.
Plastic – not so fantastic
Every week, another grotesque story illustrates the impact of plastic in the environment. A whale was recently found with 80 plastic bags in its stomach – it died, of course.
One-third of marine turtles have died or become ill due to plastic ingestion in Aotearoa New Zealand.
A 2015 study suggested that 99% of seabirds would be ingesting plastic by 2050. The authors also predicted that seabirds in our backyard, the Tasman Sea (Te Tai o Rēhua) would be the hardest hit, because of the high densities of seabirds foraging in the region, and the overlap with plastic. This not that surprising, given that the earliest observations of Aotearoa’s seabirds ingesting plastic go back to 1958.
Sentinels of ocean plastic pollution
Seabirds are particularly vulnerable to ingesting plastics because most species feed at or near the ocean surface. They forage along eddies and oceanic convergence zones – the same areas where marine plastics accumulate. The impacts of plastic on seabirds and other marine wildlife include death by entanglement. Ingested plastic can inhibit a bird’s feeding capacity, leading to starvation or internal ulcers, and eventually death.
Flesh-footed shearwater populations in Aotearoa may have declined up to 50% to around 12,000 pairs since the 1980s, and have gone extinct at some of their Hauraki Gulf breeding sites. These declines continue in spite of predator eradication and an end to harvesting on many of the islands where they breed.
Autopsies of birds caught in fisheries in Aotearoa’s waters show flesh-footed and sooty shearwaters are more likely to contain plastic fragments than other species. Plastic fragments found in New Zealand flesh-footed shearwater colonies showed a linear relationship between the number of nest burrows and plastic fragments, indicating that plastic ingestion may be a driver in their population decline.
Toxic plastic soup
In Australia, up to 100% of flesh-footed shearwater fledglings contained plastic, the highest reported for any marine vertebrate. Fledglings with high levels of ingested plastic exhibited reduced body condition and increased contaminant loads.
The chemical structure of plastics means that they act as toxin sponges, attracting harmful contaminants from the surrounding seawater, including persistent organic pollutants and heavy metals. When an animal ingests plastic, there is the potential for those toxic chemicals to leach into its tissues.
Chemicals such as PCBs and flame retardants that are added to plastics during manufacture have been found in seabird tissue around the Pacific. High concentrations of toxic chemicals can retard growth, reduce reproductive fitness and, ultimately, kill.
Sooty shearwater (tītī) chicks, which are harvested and consumed by Māori in Aotearoa, have a high potential for ingesting plastic, given evidence of plastic ingestion in shearwaters from Australia and anecdotal evidence from harvesters on Stewart Island (Rakiura). The closely related short-tailed shearwater, which breeds in Australia, has also been show to consume plastic. In one study, 96% of chicks contained plastics in their stomachs and chemical loads in their tissue.
Ocean health and human health
Few, if any, studies have specifically looked at contaminant loads derived from plastics in any species of seabird in Aotearoa. However, Elizabeth Bell from Wildlife Management International is now collecting samples of preen glands, fat and liver tissue for analysis of toxic chemicals in bycatch birds found with plastic inside them. This research is crucial to understanding the implications of the transfer of toxins to people from harvested species that ingest plastic.
Seabirds are the sentinels of ocean health. They tell us what we can’t always see about the health of the oceans and its resources that we rely on.
Plastics are sold to us on the perceived benefits of strength, durability and inexpensive production. These qualities are now choking our oceans.
In a few decades, we have produced an estimated 8.3 billion tonnes. The expedited pace of production has not been met with adequate waste management and recycling capacity to deal with it all. As a result, an estimated 8 million tonnes of plastic pollute the environment each year.
Global production of plastics is doubling every 11 years. It is predicted to be an order of magnitude greater than current production levels by 2040. The time is ripe for the initiation of an international agreement to lessen plastic pollution in the world’s oceans and save our seabirds and marine wildlife.
Plastic pollution is a ‘wicked problem’ – that is ‘a problem whose social complexity means that it has no determinable stopping point’. We can see action on stemming the flow of plastic into the ocean is gaining traction, but we need to recognise the problem is already here. So, how do we manage species conservation in a plasticene world?
I recently co-authored a paper in Science of the Total Environment (PDF here) about why and how we need to be better at linking plastic ingestion research with wildlife conservation, so that we can build tools to better manage the impacts of plastic ingestion on vulnerable species, like seabirds.
Plastic is an increasingly pervasive marine pollutant. Concomitantly, the number of studies documenting plastic ingestion in wildlife is accelerating. Many of these studies aim to provide a baseline against which future levels of plastic ingestion can be compared, and are motivated by an underlying interest in the conservation of their study species and ecosystems. Although this research has helped to raise the profile of plastic as a pollutant of emerging concern, there is a disconnect between research examining plastic pollution and wildlife conservation. We present ideas to further discussion about how plastic ingestion research could benefit wildlife conservation by prioritising studies that elucidates the significance of plastic pollution as a population-level threat, identifies vulnerable populations, and evaluates strategies for mitigating impacts. The benefit of plastic ingestion research to marine wildlife can be improved by establishing a clearer understanding of how discoveries will be integrated into conservation and policy actions.
Figure design by Jessie Borrelle @Moreorlessie http://www.creativecause.com.au/
I love to vote.
When I vote, when you vote, when we vote, our individual voice is captured and aggregated in the representatives we choose to empower. Our votes divine how we choose to treat our most vulnerable peoples, and care for our environment. In the simple action of voting, we formalise our aspirations for our future and for the future of our children – to the best of our abilities given the options.
The reason I, a woman, am able to vote in elections, to be a part of the discourse on the way our society is constructed and run is because of the women in history who marched in the streets for equality of rights. Our democracy has come a long way since the suffragists began this march for equality, but it is naive to believe that we have progressed as far as we would like to think.
What does this have to do with marching for science?
One of the most incredible things about the human species is consciousness and reflection, which not only enables us to carry out the scientific method of discovery, but change and grow our minds in response to new information.
As a society, we have achieved things that were once thought of as fanciful – people have walked on the moon, we see beyond our galaxy, we have cured debilitating and deadly diseases, and the rest….our quality of life is the highest in history (for most) – thanks to the scientific method.
Scientists are people. People make societies; societies are constructed, run and improved by evidence-based knowledge, but only when all citizens are the beneficiaries of diverse and inclusive advances. Science and society are a big beautiful interconnected network. If there is inequality in science, our science isn’t the best it can be, and if science is ignored, society suffers, we suffer.
In these current political climes, we are reminded daily that knowledge is powerful, and those that hold knowledge hold power. We see the best evidence of this under the Trump administration. The 45th president’s policy appears to be: holding truth hostage, blatantly refusing to give science a voice in policy, shutting down international scientific programs, and muzzling scientists from sharing publicly funded science with the community (particularly climate change, women’s health and vaccines). This socio-political experiment has frightening implications. We are not immune in New Zealand – you only have to look at the Land and Water forum to open the discussion about the government ignoring the advice of scientists on the sad state of water quality due to dairy intensification.
The transition from evidence-based to value-based policy can a subversive and quiet one. The question is then – are we as New Zealander’s willing to close our eyes while a few individuals make the rules according to their own needs, based on their own values, ignoring the scientific evidence and the bigger picture? Are we willing to waste the progress that the suffragettes and scientists – our Hidden Figures: Beatrice Hill Tinsley’s, Rosemary Askin’s, Kathleen Curtis’, Edith Farkas’, Constance Helen Frost’s et al – fought for, to lose the inroads they made towards equality in science and in society? I’m joining my predecessors in taking to the streets to to march for equity and reason.
I am marching for science because inclusiveness for all peoples and inclusion of science in society and governance is a common sense double down.
I am marching for science because we are science – ever-evolving experiments in understanding.
Cross posted at http://sciblogs.co.nz/guestwork/2017/03/28/march-science-nz-march/
Millions of dollars are spent on removing predators from offshore islands in the aim of protecting seabirds and island biodiversity. However, post-eradication monitoring is limited, so our understanding of how and if seabirds and their island habitats recover is also limited. In this paper, we investigated the recovery of seabirds to islands in the Hauraki Gulf, New Zealand to try and contribute to understanding these recovery processes better. The paper was published in the journal Oryx and you can find a PDF here!
Protecting seabirds is a global conservation priority
given that 29% of seabird species are threatened with extinction.
One of the most acute threats to seabirds is the
presence of introduced predators, which depredate seabirds
at all life stages, from eggs to adults. Consequently, eradication
of invasive predators has been identified as an effective
and commonly used approach to seabird conservation.
Seabird recovery following the eradication of predators is influenced
by complex and interacting environmental and
demographic factors, and there are gaps in our understanding
of species-specific responses. We reflect on the recovery
of seabirds on islands cleared of predators, drawing on the
equilibrium theory of island biogeography, and synthesize
key influences on recovery reported in the literature. We
present a regionally specific case study on the recovery of
seabird colonies (n = 98) in the Hauraki Gulf, New
Zealand, which is a hotspot of seabird diversity (27 species),
with a long history of eradications of invasive predators. We
found that on islands cleared of predators seabirds recover
over time, and such islands have more diverse seabird assemblages
than islands that never had predators. Recovery
appears to be influenced by a suite of site- and species-specific
factors. Managers may assume that given enough time
following eradication of predators, seabirds will recolonize
an island. Although time is a factor, proximity to source
populations and human activities has a significant effect
on recolonization by seabirds, as do demographic traits, colonizing
ability and habitat suitability. Therefore, integrating
expected site and species-specific recovery responses in the
planning of eradications should help guide post-eradication
If seabirds spend days, months or years at sea, how do they sleep? I talked to Jesse Mulligan at Radio New Zealand to answer that question and more about the fascinating lives of seabirds that make our country home. You can listen to the full interview here:
In June/July I was in Göteborg, Sweden for the World Environmental Education Congress. It is a beautiful city.
I’ll admit, initially I felt a little out of my element…. I am conditioned to conservation scientists, who, in all honesty are a bunch of ridiculously fun nerds. No, here there are educators, teachers, lecturers, and students [who are also a bunch of ridiculously fun geeks, just different]. It’s a rag tag bunch of folk who are undoubtedly the most important people in the world. I state that boldly, because these educators are at the coalface of hope for the future. They teach environmental literacy. Inspiring the next generation of scientists, architects, business people, and the rest about the wonder of the natural world. Informing the world’s students what in means to be alive on this planet today.
Why was I there then? well, I presented to the education world the Global Change app. A little project myself and some colleagues have been working on about plants, carbon, water and climate change – my aim is to give stomata the 15 minutes of fame to which they are so deserving of. The app was well received and there were lots of interesting and insightful conversations about the environment and the state of education and how tools, such as the app can enhance learning pathways.
I left the conference with a renewed sense of hope, there is an enormous community of educators, researchers, scientists and students working to improving environmental literacy. The next generations of students will have greater understanding, connection and appreciation for the natural world thanks to this community. It was an honor to be in the company of such a wonderful group of people.
Image Posted on Updated on
An article was published today following a national survey of how New Zealanders felt about our waterways (read the full report here: http://goo.gl/IRtmg3). Admittedly, the survey was aimed at people who are interested in fresh water fisheries – trout, salmon, and game bird hunting (it was initiated by Fish & Game), it turns out that 9 out of 10 respondents wanted to have swimmable, clean waterways, and 70% believed that the expansion of dairy farming has degraded our waterways. I am not really surprised by that, I mean, who really wants to go for a fish or a picnic in /near a filthy cow pooped stream?
We have a lot of rivers in New Zealand, which is pretty neat, so neat in fact that when you make a map of all of the rivers in New Zealand, it resembles, well, New Zealand. I made a map to show you:
The spatial extent alone makes me think that if over 52% of our waterways are contaminated, we are in trouble and we desperately need stronger legislation and action to protect the other 48% before it’s too late. Apparently, the majority of New Zealanders agree.