I S S U E 2 THE SPOTTER NEWSLETTER Our biological invasions newsletter connecting with our Western Cape spotters A U G U S T 2 0 2 0 I S S U E 3 CONTENTS WELCOME TEAM SPOTTERS 01 NEWLY DISCOVERED SPECIES 02 SPECIES TO LOOK OUT FOR THIS SEASON 03 REPORT SIGHTINGS 04 LIST OF INVASIVE SPECIES SANBI's BID Western Cape team greening the city one school at a time in celebration of Arbor Month in 2019 WELCOME TEAM WESTERN CAPE SPOTTERS Welcome to the 3rd issue of the South African National Biodiversity Institute: Biological Invasions Directorate (SANBI’s BID) Western Cape spotters update newsletter. This time we update you on two newly discovered invasive plant species and species to look out for this season in the Western Cape. SANBI’s BID targets localized invasive alien species. These species have not yet reached their full invasive potential and occur as relatively small or localized populations. Removal of these populations at an early stage of invasion will limit spread to other areas, save on future costs of control, and contribute to the ultimate goal of eradication of these species from South Africa. For more information on invasive alien species in South Africa, the latest National Status Report on Biological Invasions in South Africa is available here for download. A new book on Biological Invasions in South Africa has also just been published by Springer as part of its "Invading Nature" Series. The book is open access, and you can download it as a single file or as individual chapters. T H E D A I L Y P E E P T H E S P O T T E R N E W S L E T T E R P A G E 1 NEWLY DISCOVERED SPECIES: Melaleuca densa & Callitris rhomboidea Two newly recorded invasive Callitris rhomboidea commonly species, Melaleuca densa and known as Oyster bay cypress-pine Callitris rhomboidea, were from the Cupressaceae family, native discovered by the Friends of Tokai in in south-eastern Australia. It is a tree April 2019 invading fynbos in Tokai, that can grow up to 30 m tall. Western Cape. These species were reported on iNaturalist by Tony Rebelo and were brought to our attention by the resident taxonomist, Pieter Winter. Both species are currently not listed according to South African legislation (National Environmental Management: Biodiversity Act 10 of 2004 Alien and Invasive Species Regulations, 2014). This is the first record of these emerging invasive species in the Western Cape, South Africa. Melaleuca densa native to south- western Australia is a dense shrub that can grow up to 3 m tall. This species is not recorded on the Tokai Arboretum list, so it is suspected Impacts: CHARACTERISTICS that its introduction to South Africa This species have the ability to Leaves: was accidental or mistaken with reduce the diversity of local Its leaves are bright green, dull other introduced Melaleuca species. species and increase fire fuel load greyish-green and blue in colour. where it occurs by forming dense CHARACTERISTICS stands. Fruits/Seeds: Leaves: C. rhomboidea is wind pollinated. Its leaves are arranged in threes or Plans are under way to map the Closed cones can persist for sometimes alternate, egg-shaped extent of this population. This decades on the tree and the seed and the veins are longitudinal. species was initially identified as release follows mortality of the Melaleuca gibbosa. stem or branch to which the cones Flowers: are attached. It produces white flowers between After close examination of the August to December in its native collected specimen by the Impacts range. In South Africa, it was taxonomist in November 2019, its In its native range C. rhomboidea is observed flowering in November. identity was confirmed as regarded as opportunist species Melaleuca densa. because it grows in areas that are Fruits/Seeds: vacated by other species after M. densa grows from seeds, if killed disturbance. the seeds stored in the canopy is released to provide another generation of young recruits. T H E S P O T T E R N E W S L E T T E R P A G E 2 SPECIES TO LOOK OUT FOR THIS SEASON: Lythrum salicaria known as purple loosestrife Purple loosestrife, Lythrum salicaria, Seeds: is a tall-growing wildflower that The plant is a prolific seed producer grows naturally on banks of streams and also reproduces vigorously by and around ponds. Its flowers are vegetative means. extremely attractive to bees and butterflies in its native range. Impacts: Lythrum salicaria is an aggressive This species favours wet conditions competitor and displaces native such as swampy ground and along vegetation to form monospecific the water's edge, but will also persist stands. in dried-out land. Locality: In its native range, it grows along The species has established and is roadsides, indicating damp ground. invasive on the Liesbeek River, After several showery seasons it Cape Town, South Africa. We spreads freely, easily seen when in recently detected few plants at the flower between January and March. Grootboskloof Riverwalk in Constantia. Flowers: Characteristics It has strong, upright stems, topped Help us stop invasion early by Leaves: in summer with long, poker-like heads Leaves opposite or in whorls of three of bright purple flowers. sending us any records of this and grass green in colour. species. Kunzea ericoides known as kanuka Kunzea ericoides (Kanuka) is a fast- Impacts: growing shrub or small tree, native K. ericoides is an efficient invader of to Australia and New Zealand. It disturbed ground, and can occupy grows up to 20 m tall with a single grassland and exclude grazing trunk. animals. It form dense impenetrable stands that can limit the Characteristics regeneration of native young trees Leaves: and shrubs and shades out ground- It is often multi-trunked from the layer plants. base, trunk is slender and erect. Its leaves are alternate, bright green Locality: and linear. To date, this species has only been recorded in Camphersdrift (along Flowers: Camphersdrift River), George. Flowers are white and are crowded Fruit/seeds: on leafy side branches. The floral The fruit which is a cup-shaped capsule Help us by reporting any records of 2–4 mm long and wide. The capsule cup is covered with soft, downy this species so that we can control usually opens to release its seed when hairs. or eradicate it before it spreads. mature. T H E S P O T T E R N E W S L E T T E R P A G E 3 REPORT INVASIVE SIGHTINGS We need your help. Please report sightings of the invasive Important details to take note of are the following when plants listed in this edition to SANBI’s BID. If you spot any reporting a sighting of an invasive species; the size of the of the species please contact us before removing any part infestation, area description, diagnostic photos and GPS of the plant as that could spread the problem. coordinates where possible. We have included below the list of species on OUR radar, Lastly if you spot any invasive species that you're not sure of specifically in the winter rainfall region of the Western please inform SANBI's BID at the contact details below or Cape. Please use this list to guide your search. We have visit www.inaturalist.org also included our spotter’s membership form in the email. CONTACT DETAILS Nolwethu Tshali 021 799 8400 Email: [email protected] Sandile Mdoko 021 799 8763 Email: [email protected] EDITORIAL: SANBi’s BID Communications +27 21 799 8403 [email protected] www.sanbi.org.za MEMBERSHIP Free to join, all you have to do is complete the form attached and email [email protected] SANBI’S BIOLOGICAL INVASIONS DIRECTORATE - WESTERN CAPE TARGET SPECIES LIST: Category 1a Species Suspect Species Suspect Species Suspect Species Listed according to South African legislation Species Under Surveillance – Possible Callitris rhomboidea Melaleuca cruenta (i.e. the National Environmental Management: Eradication or Containment Targets Calluna vulgaris Melaleuca densa Biodiversity Act 10 of 2004 [NEMBA] Alien monitored by SANBI’s BID. Due to Celtis sinensis Melaleuca diosmifolia and Invasive Species Regulations, 2014). They their potential to become problematic must be controlled, or eradicated where invaders they should be controlled, or Cistus ladanifer Melaleuca elliptica possible. eradicated where possible. Cyathea australis Melaleuca linearis Eucalyptus botryoides Melaleuca parvistaminea Acacia adunca Acacia pendula Eucalyptus globulus Melaleuca preissiana Acacia implexa Acacia retinodes Eucalyptus gomphocephala Melaleuca quadrifida Acacia paradoxa Acacia viscidula Eucalyptus microcorys subsp. quadrifida Acacia stricta Agonis flexuosa Eucalyptus resinifera Melaleuca styphelioides Billardiera heterophylla Alnus glutinosa Eucalyptus sideroxylon Melaleuca rugulosa Furcraea foetida Alstroemeria pulchella Ficus carica Melaleuca subulata Genista monspessulana Anigozanthos flavidus Hypericum canariense Oenothera lindheimeri Kunzea ericoides Asphodelus fistulosus Leptospermum continentale Quercus acutissima Iris pseudacorus Banksia ericifolia Leptospermum scoparium Quercus robur Lythrum salicaria Banksia Formosa Leptospermum squarrosum Solanum laxum Melaleuca hypericifolia Banksia integrifolia Melaleuca armillaris subsp. Syzygium australe Melaleuca quinquenervia Banksia serrata armillaris Metrosideros excelsa Banksia speciosa Spartina alterniflora T H E S P O T T E R N E W S L E T T E R P A G E 4.