Non-indigenous species
Assessment of progress towards the achievement of Good Environmental Status for non-indigenous species.
The extent to which Good Environmental Status has been achieved
The UK has not yet achieved its aim of Good Environmental Status for non-indigenous species (NIS). Our ability to detect new non-indigenous species has improved but there has been no significant change in the number of new records of non-indigenous species made between 2003 and 2014.
How progress has been assessed
In the Marine Strategy Part 1 (HM Government, 2012), the UK set out “Characteristics of Good Environmental Status” for non-indigenous species. This was a high-level, qualitative description of what the marine environment will look like when Good Environmental Status is achieved.
“The risk from pathways and vectors which facilitate the introduction and spread of non-indigenous species as a result of human activities is significantly reduced, leading to a reduction in the risk of introducing new species some of which may have adverse impacts.”
The extent that Good Environmental Status has been achieved, as articulated in the criteria for non-indigenous species in the Commission Decision 2010/447/EU (European Commission, 2010), was assessed using targets set out in the UK Marine Strategy Part 1 (HM Government, 2012). Only a partial assessment of one of the targets, examining the introduction of non-indigenous species, was made using the developed indicator. Assessments relating to the spread of non-indigenous species, despite having a developed indicator, were not made due to insufficient data availability.
Progress since 2012
- This is the first UK-wide assessment of marine non-indigenous species. Insufficient information was available to enable an assessment in 2012. A limited assessment of the impact of non-indigenous species in the UK has subsequently been made.
- Locations where introductions of non-indigenous species are most likely to occur within the UK have been identified.
- Monitoring of non-indigenous species has started to be integrated into biodiversity monitoring since 2016. This has included the development of a target species list and baseline dataset. There is now greater consistency in detection effort. This will improve the quality of future data and our ability to monitor the spread of non-indigenous species.
- A Programme of Measures has been developed including Species Action Plans for high-risk non-indigenous species.
Outstanding issues
- It is expected that by the next assessment cycle, there will be ongoing significant environmental, social and economic issues presented by invasive non-indigenous species in UK waters.
- Detection of new introductions of non-indigenous species is limited by the number of locations currently monitored and the frequency at which they are monitored.
- The effectiveness of current biosecurity at reducing rates of the introduction and spread of non-indigenous species needs to be better understood.
Achievement of targets
This is the first UK-wide assessment of marine non-indigenous species, insufficient information was available to enable an assessment in 2012. The assessment of non-indigenous species was based on progress towards (a part of) one of two targets.
Table 1. Targets and indicators as established in the UK Marine Strategy Part 1 (HM Government, 2012), and corresponding assessment results.
|
Target |
Indicator |
Assessment Result |
|
Abundance and state characterisation of non-indigenous species, in particular, invasive species: reduction in the risk of (i) introduction and (ii) spread of non-indigenous species through improved management of high risk pathways and vectors. |
Community structure of non-indigenous species; trend in new records of non-indigenous species introduced by human activities |
For the Greater North Sea and the Celtic Seas: (i) there has been no significant change in the number of new records of non-indigenous species made between 2003 and 2014 suggesting the current Programme of Measures is maintaining the current status; (ii) the spread of non-indigenous species was not assessed. |
|
Environmental impact of invasive non-indigenous species: action plans are to be developed for key high risk marine non-indigenous species by 2020. |
No indicator developed at present |
No assessment made, but action plans are starting to be developed for key species. |
Non-indigenous species can be introduced by pathways such as ballast water, hull fouling and contamination of aquaculture species. The effectiveness of pathway management is best assessed using trends in the number of new non-indigenous species introduced to the UK. However, detection of new introductions requires regular and consistent monitoring at points of entry, and there is currently limited monitoring of this nature undertaken. This can result in a time lag of up to several years between time of introduction and when the species is first detected. The length of the time lag varies with monitoring effort. In the absence of effective monitoring at point of entry we have used new records of non-indigenous species reported between 2003 to 2014 as a proxy for new introductions. New records of non-indigenous species are in most cases assumed to be established species due to the time lag between introduction and detection.
No assessments of the spread of non-indigenous species have been made so far. Non-indigenous species monitoring has been integrated into biodiversity monitoring since 2016, this has included the development of a target species list and baseline dataset. There is now greater consistency in detection effort. This will improve the quality of future data and our ability to monitor the spread of non-indigenous species.
The number of new records for non-indigenous species varied between UK sub-region and year. However, there was no obvious trend in the number of new records made during 2003 – 2014. The lack of change over time suggests the current Programme of Measures aimed at controlling introductions of non-indigenous species is not resulting in a reduction in the number of species being introduced.
Indicators used to assess targets
Evaluation of this target, and the extent that abundance and state characterisation of non-indigenous, particularly invasive species, has been achieved comes part of the “Changes to Non-Indigenous Species Community Structure” indicator. This indicator consists of 3 parameters, (i) trends in the number of new introductions (ii) trends in the distribution of established non-indigenous species and (iii) non-indigenous species community abundance. The assessment conducted used the first parameter of the indicator only and is titled: “Trends in newly recorded non-indigenous species introduced by human activities in the UK’s Greater North Sea and the Celtic Seas sub-regions.” A similar assessment, using only the first parameter, has been undertaken as part of the OSPAR Intermediate Assessment 2017. As such, the indicator assessment was undertaken in each OSPAR Region (approximate to each Marine Strategy Framework Directive Sub-region) using data from the UK and neighbouring countries.
Precautionary interpretation of the data presented is required given the lack of consistent monitoring for non-indigenous species. In the Celtic Seas and Greater North Sea there was no significant change over time in the number of new records of non-indigenous species. A total of 37 non-indigenous species not previously reported in the UK Celtic Seas were first recorded between 2003 and 2014. Nine non-indigenous species were recorded in the UK Greater North Sea. The number of new records of non-indigenous species was greatest in the Celtic Seas in 2012 (followed by 2006) and in the Greater North Sea in 2004. No new records of non-indigenous species were reported in 7 out of the 12 years used in the assessment for the UK Greater North Sea and 2 out of the 12 years for the UK Celtic Seas. These results may be due to variation in monitoring effort over time, rather than a change in the numbers of non-indigenous species being introduced.
The number of new records of non-indigenous species were compared between two six-year reporting periods: 2003 to 2008, referred to here as reporting period 1 and 2009 to 2014, referred to as reporting period 2. In the UK Greater North Sea, fewer new records of non-indigenous species were reported during period 2 than during reporting period 1. The opposite occurred in UK Celtic Seas, with more newly recorded non-indigenous species reported during period 2 compared to period 1. However, these differences were not statistically significant in either region. This indicates that there was no significant change in the numbers of non-indigenous species introductions over this time period as a result of the measures in place. While there may be variation in the year of introduction compared to year the species was recorded, and variation due to monitoring effort has already been noted, neither of these factors are likely to alter the final summary. These results for UK waters are comparable to those for the wider OSPAR Regions.
Moving forward
Further development of indicators in OSPAR and associated monitoring and surveillance in key areas of risk are needed. This will increase our understanding of how the pressures resulting from non-indigenous species introduction and spread can best be minimised.
References
Acknowledgements
European Commission (2010) ‘Commission Decision of 1 September 2010 on criteria and methodological standards on Good Environmental Status of marine waters’ (notified under document C(2010) 5956) (Text with EEA Relevance) (2010/477/EU). Official Journal of the European Union L232:14-24 (viewed on 5 July 2018)
HM Government (2012) ‘Marine Strategy Part One: UK Initial Assessment and Good Environmental Status’ (viewed on 5 July 2018)
OSPAR Commission (2017) ‘Intermediate Assessment 2017’ (viewed on 21 September 2018)