South Africa s first National Status Report on Biological Invasions

Transcription

1 South Africa s first National Status Report on Biological Invasions BIM & FBIP 15 August 2017

2 This is a team effort.

3 Drafting team

4 Reference and Advisory committee Bob Scholes WITS David Richardson C I B Christo Marais DEA Peter Lukey DEA Mapula Tshangela DEA Guy Preston DEA Wadzi Mandivenyi DEA 4

5 Why a status report? Information from research and monitoring Assess the status Inform policy and management 5

6 Legal requirement The Institute [i.e. SANBI].. must.. submit a report on the status of listed invasive species. within three years, and every three years thereafter The report. must contain a summary and assessment of: the status of listed invasive species; and the effectiveness of these regulations and control measures

7 Our report goes beyond the legal requirement to consider: The status of pathways of introduction and spread The status of alien species The status of invaded areas The effectiveness of control measures The effectiveness of regulations

8 Appointment of SANBI/ C I B team Review and collate available information Arrange scientific symposium Develop suite of indicators Assign values to indicators First draft chapters Review by stakeholders and contributing authors First full draft status report Review by experts and reference committee Final status report 8

9 34 papers presented at the symposium 23 papers submitted for publication 19 papers published 76 co-authors

10 Developing indicators for the status report Based on emerging international schemes 21 indicators for: Pathways Species Areas Control effectiveness 4 high-level indicators

11 Species Alien Status A Unified Framework Blackburn et al TREE; Wilson et al Biological Invasions 11

12 Alien Species Impact the Environmental Impact Classification of Alien Taxa (EICAT) Scheme Blackburn et al PloS Biology; Hawkins et al DDI 12

13 Wilson et al. in prep. 13

14 Indicators for pathways Indicator Number of pathways Description The number of discrete pathways along which species can be introduced and dispersed Prominence of pathways The relative size of each pathways minimal, moderate, major or massive Introduction rates Number of species introduced per pathway per decade 14

15 Number of introduced taxa Pathways and their relative importance Release Escape Contaminant Stowaway Corridor Unaided Pathway of introduction 15

16 Scorecard: Pathway indicators Indicator Value Level of confidence Introduction pathway prominence Rate of introduction per pathway Minimal: 6 pathways Moderate: 10 pathways Major: 2 pathways Massive: 8 pathways Uncertain: 3 pathways 0 species: 10 pathways < 50 species: 27 pathways > 50 species: 7 pathways Moderate Low

17 Indicators for alien species Indicator Number and status of alien species Extent of alien species Abundance of alien species Categories -Present but not naturalised -Naturalised but not invasive -Invasive Species range Rare, occasional, frequent, common, abundant Impact of alien species -Species with minimal, minor, moderate, major and massive impacts 17

18 Terrestrial plants Terrestrial invertebrates Reptiles Marine invertebrates Microbes Birds Mammals Freshwater fish Freshwater invertebrates Amphibians Marine plants 2102 alien species regulated (559), or recorded in the wild, in South Africa Chart Title

19 Best available data from SAPIA Increase between 2000 and 2016 by 172, from 601 to 773 species Marked increases in distribution of nine species Spread of species under biological control has slowed down or stopped No detectable impact of control on other species Source: Henderson & Wilson Changes in the composition and distribution of alien plants in South Africa: An update from the Southern African Plant Invaders Atlas Bothalia

20 Mapped extent of occurrence (but not abundance) Common myna Mesquite Smallmouth bass Black wattle

21 Number of species that currently have major impacts in South Africa

22 Pines in fynbos Wattles In mesic areas Alien species with massive impacts Prosopis in arid areas Smallmouth bass in freshwater ecosystems Mediterranean mussel on rocky shores

23 Scorecard: Alien species indicators Indicator Value Level of confidence Number and status of alien species Extent of alien species 119 present but not naturalised 307 naturalised but not invasive 720 invasive Plants: 600 species in < 10 QDS 100 species in > 100 QDS High for plants, birds Low for the rest High for plants, birds Low for the rest Abundance of alien species Not estimated yet Low? Impact of alien species 107 species with major or massive impact Low 23

24 Indicators for invaded areas Indicator Alien species richness Description Number of invasive alien species in a particular area Relative alien species richness Relative alien species abundance Number of invasive alien species in a particular area as a proportion of all species (native + alien) Abundance (cover, biomass or population size) of alien species as a proportion of total abundance (native + alien) Combined impact of alien species Impacts on key ecosystem services 24

25 Alien plant species richness at a national scale

26 Alien species richness in invaded areas Median richness for provinces (based on quarter degree grid cells) Total richness for biomes

27 Alien plant species abundance in invaded areas Versfeld et al. (1998) confirmed what is generally accepted: Western Cape is the most invaded province (28% of area invaded to some degree) Mpumalanga (16%) Northern Cape (14%) KwaZulu-Natal (9%) These estimates, besides being crude, are more than 20 years out of date, and both the extent of invasions, and the relative dominance of species, have changed considerably since then, but there is no effective monitoring of this.

28 Example of area impact reduction in mean annual runoff Source: Le Maitre et al Water SA

29 Scorecard: Invaded areas indicators Indicator Value Level of confidence Alien species richness Relative alien species richness Relative alien species abundance South Africa: 2102 species Breakdowns per biome Example 300/7000 for fynbos biome No data High for vertebrates and plants Low elsewhere Moderate n/a Combined impact of alien species Surface water runoff: million m 3 /yr Livestock carrying capacity: large livestock units Biodiversity intactness: 3% Low 29

30 Indicators for effectiveness of control measures Type of indicator Inputs Outputs Outcomes Description Money spent Planning coverage Number of pathways, species or areas that are actively managed, as a proportion of all pathways, species or areas requiring management Estimated effectiveness (for each pathway, species or area) in categories (effective, partially effective, ineffective)

31 Pathway management Only one entry point monitored by DEA at present

32 Indicators of effectiveness of control measures: Pathways Separate measures by DAFF for agricultural pests could also reduce the rate of arrival of new environmental problems. Insufficient data to link the impact of these measures to the outcomes.

33 Terrestrial plants Marine plants Mammals Freshwater fish Reptiles Amphibians Birds Marine invertebrates Freshwater invertebrates Terrestrial invertebrates Microbes How many species do we manage? (number listed, number managed) Chart Title Series1 Series2

34 What proportion of the population of managed species do we get to? Data supplied by Andrew Wannenburgh: DEA 34

35 Indicators of effectiveness of control measures: Species 9 historical eradication programs three succeeded (cats on Marion Island, two terrestrial invertebrates) six failed More eradications expected over the coming decade. Biological control a major success - 15 species under complete control, 19 species under substantial control. Management programmes have been developed for a small number of established invasive alien species, but none have been implemented. Their effectiveness therefore cannot be assessed.

36 Area control measures Inputs ~ R1.5 billion/yr Outputs 2.8 million ha cleared, 8 million ha followed up (over 20 years) Outcomes Localised successes But continued growth in populations of most species at a national scale 36

37 Contributing factors to success Ongoing direction from a diverse project steering committee Rapid response team Focus on areas of low infestation Very flexible management approach Regular monitoring In addition the team was only paid following completion of a contract and after a thorough inspection of the quality of the work by the Project Manager. 37

38 Effectiveness of regulations 100s of permits issued, risk assessments completed, notices served Low levels of compliance with requirements to submit notifications, control plans, research information Huge capacity constraints Too early to gauge effectiveness

39 Scorecard: Intervention effectiveness indicators Indicator Value Level of confidence Input: Money spent ~ R2 billion/yr Moderate (underestimate) Input: Planning coverage Output: Proportion managed Outcome: Management effectiveness 4% 77% of pathways 24% of species 0.36% of land 8% effective 58% partially effective 34% ineffective Low Moderate Moderate Moderate Low Low Low

40 Scorecard: High-level indicators Indicator Value Trend Level of confidence Rate of introduction of new species per decade 70 Low

41 Scorecard: High-level indicators Indicator Value Trend Level of confidence Rate of introduction of new species per decade Number of species with major impacts 70 Low 107 Low

42 Scorecard: High-level indicators Indicator Value Trend Level of confidence Rate of introduction of new species per decade Number of species with major impacts Percent of area experiencing major impacts 70 Low 107 Low 5% Low

43 Scorecard: High-level indicators Indicator Value Trend Level of confidence Rate of introduction of new species per decade Number of species with major impacts Percent of area experiencing major impacts Effectiveness of control measures (%) 70 Low 107 Low 5% Low 5.56% Low

44 Thank you