Invasive Alien Species

Measurement and availability of data to support the analysis of the costs and benefits of IAS management

The range of costs and benefits and the different currencies in which they are measured are large.  What methods have been used to measure key elements of these costs and benefits?  What existing data sources or models are available to help?  How do we balance the needs for large volumes of data on large numbers of species with the practicalities of decision making?  When should we use empirical data or rely to expert elicitation?

Dear all,

A couple of case studies were prepared for the Caribbean region under the GEF-funded project "Mitigating  the  Threats  of  Invasive  Alien  Species  in  the  Insular  Caribbean (MTIASIC)"

The approach chosen was:
• All  costs  (losses)  and  benefits  (gains)  are  considered,  including  potential  impacts  on  human  lives  and  the environment;
• Costs and benefits are valued from a whole-of-society perspective rather than a private perspective;
• To the extent possible, costs and benefits are expressed in monetary terms; and
• Costs and benefits that are realised in the future are discounted to obtain present values.

The 5 case studies were:
1. Casaurina on Eleuthera Island, Bahamas;
2. Feral donkeys on Cabritos Island, Dominican Republic;
3. Whitetop in Waterloo, Trinidad and Tobago;
4. Giant African Snail in Trinidad, Trinidad and Tobago; and
5. Red Palm Mite in Nariva Swamp, Trinidad and Tobago.

Please see
http://www.ciasnet.org/2015/04/28/economic-impact-of-ias-case-studies/ and/or download the full report at
http://www.ciasnet.org/wp-content/uploads/2015/04/Economic_Impact_of_IAS_in_the_Caribbean_2014.pdf

There was also a study done by CABI in Africa.  I'm trying to source it form the authors, as the published link is broken.

Best wishes,
Ulrike

Ulrike
Many thanks for this, good to see examples of the full economic cost-benefit analysis of species with net present values and benefit:cost ratios.  Where these figures can be derived there are considerable strengths to this approach.
Pete

I now managed to obtain the report from Africa - attached.

I've been too busy the last couple of days to follow the discussion, but have non-parametric assessments been considered for cases where there is a high intrinsic value (or cost) that cannot properly be captured by economic metrics alone?  In a different context, I've made good experiences with combining non-parametric scored with parametric ones, using multi-criteria matrices.  They're a great tool to prioritize action and/or arrive at a consensus in an objective and transparent manner - very useful for stakeholder groups with  contrasting interests.

Ulrike

Thanks Ulrika
Good to see the African report and their approach to the integration of the costs of impacts and management.  On your further point about multi-criteria analyses, I think that they have a great deal to offer, particularly their ability to combine criteria measured in widely different currencies to support decision making.  They also have the scope to combine quantitative information on cost, with more qualitative measures such as the assessment of humaneness and public acceptability in a single approach.  Many current approaches to risk assessment use this approach, combining evidence and expert opinion to score species under a variety of criteria, and the same can be applied to risk management considerations.
Do others have experience and examples of the use of these multi-criteria approaches to support decisions making?
Pete

Dear All

Cost-benefit analysis is regarded as an important decision support framework for the management of invasive alien species in South Africa which requires identifying species, their associated risks and appropriate management options. In this case SA has conducted a study that considered Economic consequences of invasion: The value of benefits of Prosopis was found to marginally exceed the cost of impacts, but this was predicted to change within a few years as Prosopis continues to spread, resulting in net negative impacts that will grow over time.

In most cases control strategies are often compared based on cost benefit models which are rendered more accurate by knowing how effective control measures are per unit of cost. Because the cost and effectiveness of control methods can vary non-linearly with the size of the invasion, the effects of methods should also be related to the spatial and temporal scales of application.

The underlining factor is that managing alien species once they have been introduced is difficult and costly, therefore is often more efficient and cost-effective to prevent their introduction.

Bellow is some of the studies that we may wish to consider

Regards,
Ntakadzeni

Thank you Ntakadzeni
Good to see the use of these applications in South Africa and some impressive benefit:cost ratios - I particularly like the figure of 4333:1 for golden wattle!
Pete

Thank you Ntakadzeni!

I agree with you that the cost of management once the species has been introduced is greater than the cost of prevention.

Developing a strategy for cost-benefit analysis is important, and it is necessary to consider not only border introductions but also case of movements within the national territory.

In Ecuador, a risk assessment system is being developed for exotic species and a tool for cost-benefit analysis is important to help decision-making regarding the management of these species.

Victor.

Where is the evidence to support this. You have to prevent many species not knowing which one will cause harm, while quick management post introduction for the few that seem to be impactful may be less costly. Triage in decision making is necessary at some point

Hi,

Pre-boarder risk assessment may assist in this regard and the EDRR may pick up that which was missed by pre-boarder.

Ntaka

Agreed. In such circumstances the BCA of undertaking a biological control program for example always comes up in favor of the program.

Dear all,

My question about this thread is on the necessary data for cost-benefit analysis. What kind of data we should have? I believe this is important, so we can produce more suitable data for this type of analysis.
I believe Ntakadzeni’s comment helps with this matter once we should consider different spatial and temporal scales for these analyses.

Cheers,
Tatiani

Databases on the costs of IAS eradications

Eradications are particularly useful to consider as a source of data on management costs as they have a clear definition of their objectives and success – something much less simple to define for long-term management programmes. This should support comparisons of the costs of eradications between environments and taxa as our data sources increase. Sources such as the Database on Island Invasive Species Eradications http://diise.islandconservation.org provide information on eradications undertaken in a sector, but don’t include information on associated costs.

The scientific literature includes a number of published reviews of the measures and costs of different IAS eradications in relation to scale, including of plants (Rejmanek and Pitcairn 2002); forest insects (Brockerhoff et al. 2010); mammals from islands (Martins et al. 2006, Howald et al. 2007, Holmes et al. 2015, 2016) or larger land masses (Robertson et al. 2017). The Gerda website has collated information on the costs of eradicating terrestrial invertebrate pests. (http://b3.net.nz/gerda/index.php).  It would be good to hear of our sources for eradication cost data.  There are a range of other project specific reports but these different sources need to be pulled together – something we are working on. 

There are clear conclusions from these papers, that the area over which eradication is undertaken is the main determinant of total cost, that there are upper limits to the area over which successful eradications have been achieved, and these vary between different taxa and control methods, and that the costs per unit area vary for different taxa and environments.

However, this literature contains a number of shortcomings, such as under-reporting of failed eradications (Bradshaw et al. 2016), or that very few studies (Gardener et al. 2010) systematically document the cases where eradication could have been applied but was not attempted. However, these reviews document how costs change in relation to area, and record the areas of the eradications.  These provide a useful and growing data source on management costs.

Bradshaw, CJA, Leroy, B, Bellard, C, Roiz, D, Albert, C, Fournier, A, Barbet-Massin, M, Salles , J-M, Simard, F, Courchamp, F. (2016). Massive yet grossly underestimated global costs of invasive insects. Nat. Commun. 7, 12986 doi: 10.1038/ncomms12986
Brockerhoff, E.G., Liebhold, A.M., Richardson, B. and Suckling, D.M., (2010). Eradication of invasive forest insects: concepts, methods, costs and benefits. New Zealand Journal of Forestry Science 40 suppl. S117-S135
Gardener, M. R., Atkinson, R., & Rentería, J. L. (2010). Eradications and people: lessons from the plant eradication program in Galapagos. Restoration Ecology, 18(1), 20-29.
Holmes, N.D., Campbell, K.J., Keitt, B.S., Griffiths, R., Beek, J., Donlan, C.J. and Broome, K.G., 2015. Reporting costs for invasive vertebrate eradications. Biological Invasions, 17(10), pp.2913-2925.
Holmes, N.D., Campbell, K.J., Keitt, B., Griffiths, R., Beek, J., Donlan, C.J. and Broome, K., 2016. Correction: reporting costs for invasive vertebrate eradications. Biological Invasions, 18(10), pp.2801-2807.
Howald, G., Donlan, C., Galván, J.P., Russell, J.C., Parkes, J., Samaniego, A., Wang, Y., Veitch, D., Genovesi, P., Pascal, M. & Saunders, A. (2007). ‘Invasive rodent eradication on islands’. Conservation Biology, 21(5), pp.1258-1268.
Martins, T.L.F., Brooke, M.D.L., Hilton, G.M., Farnsworth, S., Gould, J. & Pain, D.J. (2006). Costing eradications of alien mammals from islands. Animal Conservation, 9(4), pp.439-444.
Rejmánek, M. & Pitcairn, M.J. (2002). ‘When is eradication of exotic pest plants a realistic goal.’ Turning the tide: the eradication of invasive species, pp.249-253.
Robertson, P.A., Adriaens, T., Lambin, X., Mill, A., Roy, S., Shuttleworth, C.M. and Sutton‐Croft, M., 2017. The large‐scale removal of mammalian invasive alien species in Northern Europe. Pest Management Science, 73(2), pp.273-279.

Pete

Very few eradication programs also look to see whether the recognized impact has been averted.i.e. the goal is species removal rather than the opportunity cost leading to a biodiversity benefit. Only half you need for a CBA. We need to encourage better impact monitoring and evaluation  

Andy

Thank you for this very valuable information and references. This is very helpful!There are other technical reports that I know of, but they are not in English, which limits their spread.

Melanie Josefsson
Swdish Environmental Protection Agency

Dear colleagues,

During the course of our almost 5 years IAS project funded by GEF through UNEP/CABI Program, we had use CBA approach as a tool to assist us in choosing the best management option to control the massive invasion of Acacia nilotica in Baluran National Park in Indonesia.  Similar to some of our colleagues that we have problem to circulate the article / journal as it is written in Indonesian language.  Results from our study showed that CBA approach will only be useful if we can collect these following information: built good assumption from current and expected/ideal situation, start with correct questions to be addressed, able to identify actors and users, availability of data on the stakeholders perception with regard to the presence of Acacia in particular area (monetary and non-monetary values), potential indirect and direct negative / positive impact to environment and community (social) and determine alternative solution to be compared with.  Final results indicated an extremely huge financial lost   due to Acacia infestation in the savanna ecosystem in this national park. This extreme financial figure would be far reduced if we are able to correctly assess the values of each measured parameter, which is quite difficult as some of them are very vague.  The other thing is, CBA is often done quite late or in the middle of invasion process, and thus difficult to compare with the ideal situation. Or, same important elements to take into account has already been gone due to various problems. It is also good for us here if we can share study on CBA of particular IAS in your country so that we can learn from each other on how we can best developed or study the economic and social lost due to IAS using CBA approach.
Hoping to receive any article discussing the use of CBA for IAS cases.

Titiek Setyawati
PM for Green Infrastructure Development
Wildlife Conservation Society (WCS-Indonesia Program)

Hi Titiek

I have attached one of a weed we worked on. Best wishes

Andy

Hi Pete, perfect overview.

Indeed I believe we can learn a lot from good documentation and registration of management interventions with costs, methods etc. In Europe, the reporting obligations towards the member states offer some prospect for better documentation but there is a long way to go I think before more comprehensive, openly accessible data will be available that allow for instance decision support such as eradication probability models.

Yet member states (at least my country but many others I assume) are currently reporting cases of management of Union List species, with costs associated. Perhaps this information could be opened up. For now, there is only notification e-infrastructure available, and the reporting on interventions in there is crude and not very detailed (I doubt it would allow calculating a cost per unit area for instance), but at least the objective for every notification is clear (eradication).

I wonder if, as a starting point, interventions could be traced back from Life project reports on specific IAS projects and their budget sheets.

Would be good if we could start to build up data bases of species level RAs that have already been carried out across different jurisdictions. Given there are many cosmopolitan pests, weeds and pathogens this would help when a new jurisdiction wants to conduct and RA against an IAS where and RA already exists. Perhaps the ISSG could facilitate this.

Andy

Absolutely! The IAS team at the European Commission hasalso expressed a need for a database of Risk Assessments that have been done, but as far as I know, no one has done anything to make this happen.

Best regards
Melanie

The UK have published their methodology for risk analysis, and the risk assessments that form part of this.  These can be found on their NNSS website under species information>risk analysis>risk assessment
http://www.nonnativespecies.org/home/index.cfm. 
This lists over 100 complete species assessments.
The EU have also published a series of risk assessments to support their listing of Species of Union Concern which are publically available through their CIRCABC website, although users need to register to gain access.
Pete

Current Australian Pest Risk Assessments (PRAs) covering agricultural and environmental risk are also published through the Australian Government Department of Agriculture and Water Resources web site http://www.agriculture.gov.au/biosecurity/risk-analysis/

Andy

Hi pak Andy...thanks for the info and i am still working to support the Government of Indonesia in tackling IAS cases.  Getting serious now and try to develop policy and procedures for biosecurity.  And of course, still struggling to collect data on IAS spread and the environmental and social impact. 

cheers,
TS

Hi all,

Interesting discussions here, thank you. I agree databasing (and versioning) risk and impact assessments would be a good idea. I can see a number of applications of those data:

- to flag species from neighbouring regions, similar climates or bioregions that were considered high risk.
- to properly fill or extend on the field "IsInvasive" (a darwin core field) in the GRIIS checklists (see Pagad et al. 2018). Here, the notion between current and potential impact becomes important. Currently the process is you need evidence of impact to flag it as invasive = when it's already too late to act. Perhaps it's more proactive to include potential impact in those checklists.
- for research purposes

In Belgium impact assessments were performed by the BFIS for a number of species, and more detailed full risk assessment for a limited set of species (http://ias.biodiversity.be/species/risk), some of which have been used to justify inclusion of species on the Union List (e.g. Sciurus niger).

To be useful, such RA database would have to include the species, the date it was performed, the risk assessment area, information on quality control (peer review, expert elicitation etc.), who performed it, the protocol used, their outcome, a standardized notion of risk etc. In Europe, RAs for listing need to adhere to standards (Roy et al. 2018, now transposed in an implementing act) so that might be a way to start thinking about proper metadata.

The RAs for the Union List of the EU Regulation are open to all via the commission's website http://ec.europa.eu/environment/nature/invasivealien/index_en.htm ("The risk assessments underpinning this proposal are available here."). I believe this link should work without registration.

Hi Tim
Thanks for this, and good to have your input.
I agree with your points about risk assessment, there is a lot of experience now of using these methods and we should consider how we can best share them internationally and agree metadata and standards.  As we have discussed before, risk assessments are only a part of the decision making process for management, and it would be good to hear more about how you have used risk assessment alongside other methods in Belgium.
Pete

Hi, there are IUCN technical reports for several species listing the costs of eradication etc...Im attching the hogweed one, but it will be updated in a close future...
there are ca more 10 other species and I think they are adding more...