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Environment and Communications References Committee
Threat of marine plastic pollution in Australia

WOEHLER, Dr Eric John, Convenor, BirdLife Tasmania, BirdLife Australia


Evidence was taken via teleconference—

CHAIR: Welcome. Information on parliamentary privilege and the protection of witnesses and evidence has been provided to you. Before we proceed, do you have any comment to make about the capacity in which you appear?

Dr Woehler : BirdLife Tasmania is a regional branch of BirdLife Australia, on whose behalf I prepared the submission.

CHAIR: I invite you now to make a brief opening statement, and then the committee will ask questions.

Dr Woehler : Birdlife Australia appreciates the committee's interest in our submission and welcomes this opportunity to provide additional information to the committee in its inquiry. Our submission was not what we expected to deliver when we commenced our response. We believed that we would find a substantial volume of scientific literature detailing the ingestion of microplastics by shorebirds—as coastal, intertidal feeders—around the world, particularly in Europe and North America. But, unfortunately, we were unable to locate a single scientific study from anywhere in the world. Such a gap is remarkable and highly significant. The absence of such studies reinforces that there is still much to learn from our environment, particularly the marine environment.

Many of our resident and migratory shorebirds are decreasing—some at catastrophic rates—as evidenced by their critically endangered status under the EPBC Act. We believe that ingested microplastics and the absorbed chemicals associated with them are an unrecognised threat to resident and migratory shorebirds in Australia and elsewhere around the world.

Please note that I am shown as the convener of BirdLife Australia. I am not. I am the convener of BirdLife Tasmania, a regional branch of BirdLife Australia. I would respectfully ask that the committee minutes and proceedings be corrected to reflect my true status.

CHAIR: Thank you, Dr Woehler. I will go to Senator Whish-Wilson.

Senator WHISH-WILSON: Firstly, thank you for your submission and for appearing here today, and thank you for all the work you have done over the years. Your single-minded focus on the protection of shorebirds is quite remarkable.

I asked several questions in Sydney and today about the amount of research that has been done. We have had some discussion around the quality of research. Could you give us an idea of the kind of shorebirds that would be impacted by marine debris.

Dr Woehler : We would argue that every single shorebird that feeds on Australia's foreshore or coastal areas would potentially be at risk from ingesting microplastics. It is clear from the literature around the world that these microplastics are not just confined to marine environments; they are also found in freshwater and estuarine environments. These foreshore areas—estuarine, freshwater and marine—are all used by migratory and resident shorebirds in Australia.

Senator WHISH-WILSON: The committee has learnt that in 2009, under EPBC law, marine debris was classified as a threatening process, and a threat abatement plan was put in place. The primary focus of that law is on the protection of threatened species, so if it is not classified as a threatened species it does not get included in the overall strategy. Are there any shorebirds or migratory birds that would be threatened species?

Dr Woehler : Yes. We have detailed those species in our submission on pages 8 and 9 through to 11. A number of our resident species, such as the hooded plover, are now listed as a threatened species under the EPBC Act. We are seeing a long-term decrease in the numbers of hooded plovers, certainly in eastern Australia. A number of migratory shorebirds have been listed as threatened under the EPBC Act, such as the eastern curlew, which is listed as critically endangered. At the moment I believe there are six additional species of migratory shorebirds currently being assessed by the Department of the Environment for upgrading to 'threatened' under the EPBC Act as well.

Senator WHISH-WILSON: In terms of what little scientific research has been done to date, most of the work that we have heard about has been focused on shearwaters and albatrosses. Is that your understanding?

Dr Woehler : That would be a fair reflection of the current status of knowledge, yes.

Senator WHISH-WILSON: These kinds of birds are sentinel species, so they act—pardon the pun—like a canary in the coalmine. So is it your feeling that there would be other birds impacted that have not been studied?

Dr Woehler : I would agree with that assessment. We know, full well, the complexity of marine food webs, and we know from the work on the invertebrate sampling that has been done around the world that many of the food species that are consumed by shorebirds in Australia have been shown to ingest plastics. So it is a reasonable hypothesis or prediction to make that these birds would also be susceptible to ingesting the plastic through their food.

Senator WHISH-WILSON: We have certainly had some interesting and quite startling and disturbing evidence around plastic in all sorts of marine life. The Department of the Environment said today that the issue of microplastics is really only just an emerging issue. Why do you think there hasn't been any research on the impact?

Dr Woehler : I would agree that it is an emerging topic or an emerging threat that has been identified. The only paper that I could find that even mentioned or identified marine plastics and microplastics as a possible future threat was published in 2012 in a global review. That was the first and only mention that I have been able to identify that specifically targets microplastics as a possible future threat to shore birds. I suspect that, with microplastics, it is literally because of their small size, by definition, that this is a threat that has been overlooked—not just to birds but to the marine environment more generally.

Senator WHISH-WILSON: Thank you. We know that the Department of the Environment are revisiting the wildlife conservation plan for migratory seabirds. Would it be your recommendation for the committee that they include the threat of marine plastics in that document?

Dr Woehler : I believe it would be a useful strategy or a useful leverage to include in the wildlife conservation plan, on the basis that it would then provide additional focus and potential funding for research on the issue of microplastics in shore birds.

Senator WHISH-WILSON: You also recommend that the Commonwealth government adopt the 2009 draft guidelines for 36 migratory shore species, which is an EPBC Act policy statement. Can you explain to the committee what these guidelines are and what the effect of adopting them would be?

Dr Woehler : I am delighted to say that, sometime in the middle of December last year, the federal government actually adopted the EPBC policy statement 3.21 when they updated the wildlife conservation plan. That recommendation has already been implemented by the federal government. We understand that the draft was in existence since 2009 and we felt it would be useful to include the potential threat of microplastics to migratory shore birds as part of an overall national conservation plan for the species.

Senator WHISH-WILSON: Excellent, thank you for that. I do not think the committee was aware of that, so it is good to get that update. You state in your submission that the lack of original, primary scientific research on the ingestion of marine microplastics by shore birds is an opportunity for researchers. Do you have any suggestions about particular species or locations that would be best studied and are you consulting with anyone on this, like the CSIRO or other researchers?

Dr Woehler : I will answer the second part of the question first. We have had a number of discussions here in Hobart with colleagues from the university and with CSIRO to undertake a pilot study in the Derwent Estuary to see if we can establish the protocols for the identification of, or the presence of, marine microplastics in the food chain in the Derwent Estuary. We hope to have one or more undergraduate students involved in that research this calendar year.

As far as the broader question of which species and which location, a lot of that will be determined by the accessibility of sites and the accessibility of, potentially, the carcasses of migratory shore birds for an examination of their stomach contents. To obtain a representative sample of the presence or absence of microplastics and the extent of the microplastics in the stomach of a bird requires the death of the bird, so it would be a matter of obtaining permits and of the ethical considerations of killing a bird specifically to obtain a stomach sample to look at the presence or absence of microplastics.

Senator WHISH-WILSON: Sometimes you see dead birds on the beach that have been there for some time and you can see evidence of what is in their stomachs, if it is plastic. Have you seen any anecdotal evidence of that kind of thing? I know it gets washed away by waves.

Dr Woehler : We have had a permit for the last two calendar years to collect carcasses that are fresh and intact from beaches in Tasmania, specifically to look at, among other things, plastics in stomach contents. So far, I am happy to say, in the last two years we have not come across fresh birds that were in a position to be collected for such analyses, but we have proactively obtained a permit to collect those carcasses, should the opportunity present itself.

Senator WHISH-WILSON: Okay. In terms of potential toxicity, whether it was through eating seafood or direct ingestion of plastic, would there be any reason why studying one bird species, like shearwater, would not be similar to other bird species?

Dr Woehler : The diet of the different species of shorebirds and seabirds varies to some extent. So you would have to take representative samples from a number of different species to gauge how indicative they are of the broader system and the levels of contamination in different parts of the marine food web.

At the moment we are fortunate that there are a number of researchers working on shearwaters in particular in Australia. They are providing an early-warning signal about the state of the marine system in terms of marine microplastics and the potential for the chemicals associated with them. But that is just the first step. We would not wish to make inferences or broad-spectrum generalisations about the marine environment based on a single species.

Senator WHISH-WILSON: Thank you. We heard today from CSIRO that even with a species like shearwater, which we have had some studies on, we cannot categorically state that choking, starvation or ingestion has been the direct cause of mortality in some of the birds that have been studied. Is it your suggestion to the committee, as a scientist, that we should adopt the precautionary principle in relation to the management of these issues?

Dr Woehler : I totally endorse the adoption of the precautionary principle. To a large extent, direct observation is precluded by the fact that, certainly, the seabirds and the migratory species spend a lot of their time at sea or away from colonies or away from anywhere where we have the capacity for direct observation. So, even if an ingestion event directly caused the death of an individual bird, it is almost certainly going to be in an area or location that would not be able to be observed directly by researchers or by anyone in general. So the adoption of precautionary principles, where we err on the side of caution and assume the worst until and unless we are shown otherwise, would be completely appropriate.

Senator WHISH-WILSON: Do you have any thoughts on the sources of the kind of plastic that you have seen in your work, or any observations for the committee? I know you are a scientist, so you do not have to—

Dr Woehler : We know that the persistence of these plastics is measured, certainly, in decades, if not centuries. And there is also an extensive degree of mixing, so it is very difficult to point the finger at any one particular point source or point location for this material. We can simply recognise that there is a broad spectrum of sources, directly and indirectly providing material into the marine environment. Then, through breakdown by waves and biological breakdown by animals, this material is forever becoming smaller in size and becoming more widespread in the marine environment.

Senator BACK: I have listened carefully to the exchange, Dr Woehler. By 'microplastics' I understand that we are talking about plastics that are not visible to the human eye.


Senator BACK: We are not? Senator Whish-Wilson is correcting me on his way to the toilet! There is no point trying to go to the toilet that way, Senator Whish-Wilson; the door is locked! You have to come round this way. I am just helping him out, Dr Woehler!

Dr Woehler : Good on you!

Senator BACK: Even at post mortem, how readily would somebody be able to identify microplastics in the gut or the stomach of the dead birds?

Dr Woehler : It would require some laboratory equipment. Relatively simply, you would extract the entire digestive tract—from the back of the mouth, the top of the throat, through to the cloaca of the bird—and then you would have to wash the contents of the digestive tract through a series of filters, ultimately to the point where you may use filter paper to retrieve very small particles.

Senator BACK: That is what I was getting at. So really, rather than it being the task of a well-meaning amateur, it really has got to be the task of a person who is (a) competent, (b) with the necessary equipment, and (c) within the time frame where you are likely to get a result?

Dr Woehler : Yes. The well-meaning citizen can certainly be involved in the collection of specimens from a beach or from the foreshore, but I agree with you that the collection of material from the carcass of the bird requires some degree of technical proficiency and a fair degree of laboratory equipment.

Senator BACK: Taking on board, as you said, the ethical issue of actually killing a bird for the purposes of research, it really then comes down to either a bird that is injured or for some other reason has to be euthanased, or one that is relatively freshly deceased.

Dr Woehler : Indeed. Certainly there are encounters of such birds on the foreshore, but the numbers are relatively low. It would be a challenge to obtain statistically valid results from a very small sample of birds.

Senator BACK: Senator Bullock and I are from Western Australia, and I have had a very long interest in migratory birds. At Roebuck Bay at Broome there are a significant number of migratory birds that arrive and are the subject of netting, observation and examination, and have been for many years. It just causes me to ask: do we have any data from Roebuck Bay over time which can assist us in coming to an understanding of this likely impact?

Dr Woehler : Roebuck Bay would certainly present an opportunity. There is, unfortunately, a small or a low level of mortality or injury associated with cannon-netting of these birds. There would be an opportunity for those birds that are injured or killed through the catching efforts up at Roebuck Bay, and potentially other parts of Australia such as Moreton Bay in Queensland, to provide a sample.

Senator BACK: I am quite derelict; I ran Rottnest Island for many years in the late eighties and nineties, and, of course, we had a significant number of migratory birds—particularly the little stints that used to come down from Siberia. They weighed 30 grams and lost a third of their body weight. They were so light they could not come on the thermals—they actually flapped their wings. We banded them, and there were some birds that actually made a second or third trip.

Senator BULLOCK: Carrying a band?

Senator BACK: Carrying a band—they were very light bands. But I have no recollection, I must say, of being focused on that at that time or indeed anyone bringing dead birds in to me to have a look at. It is a very interesting discussion, and it emphasises the point you are making: that we are deficient in valuable research in terms of getting useful data.

Dr Woehler : Yes, indeed. The reality is that, if there were encouragement from the government to collect such data as we needed to have an informed debate, the cost would not be big and it would not take that many years in order to collect the information to have that informed debate.

Senator BACK: That is right. I should finish the story by saying the stints used to feed on these microscopic animals called 'brine shrimp'.

Dr Woehler : Artemiidae. Yes.

Senator BACK: The brine shrimp existed in our lakes because of what is called a 'meromictic' effect. I will have to explain to Hansard afterwards the spelling of the word 'meromictic'. Thank you for your evidence, Dr Woehler. It has been very, very interesting.

Dr Woehler : Thank you very much.

CHAIR: I might just follow on from that theme, before I hand over to Senator Bullock. I noticed in your submission you had a summary of some recommendations. Your first recommendation was about the Commonwealth government supporting directed and detailed scientific research. I had a look in the BirdLife Australia annual report and I note in there that for the year 2014 there was consolidated research project income of $2,349,579. I am interested to know the source of that income. You just talked about research and what sort of money we might be looking at to do proper research, so I am interested in that angle.

Dr Woehler : I cannot give you a detailed breakdown of the source of income for the BirdLife Australia income. That is something that you would have to direct to the BirdLife Australia national office in Melbourne. I do recall that there was certainly some federal funding for specific research projects. So the money that BirdLife Australia raises for research comes from government, non-government and philanthropic sources.

CHAIR: Are you able to take that on notice and provide that back through BirdLife Australia?

Dr Woehler : I can take that on notice if you give me some specific details as to what is required. I am happy to do so.

CHAIR: It is the breakdown of the sources of that particular research income in your annual report. I also note in the annual report that you had donations of $1.196 million dollars. Does any of that go to research at all?

Dr Woehler : I cannot tell you. I am not involved in the budgeting of the organisation at all.

CHAIR: No, that is fine. I understand that. In light of your recommendation 1, are you able to put some sort of figure on what you think would be the sort of figure you think we need to do that directed and detailed scientific research?

Dr Woehler : I am happy to prepare some indicative figures, yes.

CHAIR: That would be fantastic.

Senator BULLOCK: Dr Woehler, I will not take up much of your time. In looking at your four recommendations, not only recommendation 1 but all four of them focus on the need for more research. Your points are well made, and I take them.

Dr Woehler : Thank you very much.

Senator BULLOCK: That is the first point. The second point is to commend you on your correct use of the plural of 'focus'. The number of 'focuses' around here is driving me to distraction.

Dr Woehler : Senator, you would be delighted to know that I am a pedant when it comes to the English language.

Senator WHISH-WILSON: Thank you again, Dr Woehler. Keep up the good work.

Dr Woehler : Thank you kindly.

CHAIR: Dr Woehler, I thank you for your submission and your attendance here today. It has been very interesting. Thank you very much for your time.

Dr Woehler : You are welcome. Thank you very much for your interest.

Proceedings suspended from 11:48 to 12:14

CHAIR: We have had trouble contacting the Law Council of Australia for the teleconference, so the committee will now adjourn. That concludes today's hearing. I thank all witnesses for their informative presentations and now declare the hearing closed.

Committee adjourned at 12 : 14