Biodiversity management plan for the western leopard toad amietophrynus pantherinus
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Inappropriate actions: Notes: 1. Walls should preferentially have border of plants, and not a hard surface right up to their edge. 2. Law enforcement is perceived to be non-existent in places. Residents could report non-compliance to authorities.
Inappropriate actions: Notes: Threat 6. Mowing Desired Objective: Mowing of opens spaces usually peaks during spring and early summer, most especially the first hot spells when growth may be phenomenal. Unfortunately, this often coincides with the departure of toadlets from the Breeding sites. Mowing is thus contraindicated during the toad migrations, which is usually before the main growing season, and during toadlet emergence. Thus mowing before August is acceptable as far as toads are concerned. After the toads have left the Breeding sites there is a window for mowing until the toadlets leave the pools, when mowing within 1km radius of Breeding sites and hotspots should be suspended for at least a week. Thus – coupled with allowing bulb and annual seed set, mowing should be suspended until the end of October. However, mowing should cease for 1km radius from Breeding sites the moment toadlet migration is noted. Mowing is far more toad and toadlet friendly if the grass it cut to a height of 100mm and not cut right to the ground, and higher cuts should be used until the onset of the really dry season and most toads are aestivating. Weedeaters are particularly bad in terms of killing toads and other animals. They also kill toads in gutters, corners, adjacent drains and other such toad “hideouts”. In these areas weedeaters should always leave a 100mm stubble. Even in some safe hideouts toads will emerge if the disturbance is prolonged: mowing should proceed in one direction and labourers should not converge. Apparently a moratorium on mowing from June to October is already in place around breeding sites.
Inappropriate actions: Notes: 1. There is a conflict here as tightly mowed verges allow toads and toadlets to move much faster. However, toadlets especially are exposed to desiccation and predation when moving through tightly mowed verges. 2. The city employs many contractors, and often during high season (October and November) these work on weekends to keep up with the workload. Tighter compliance of contractors within 1km of Breeding sites is required, and all contractors should attend an annual refresher course on the significance of toads and other fauna and flora in road reserves, verges and public open space. Contractors should be encouraged to feedback their observations and feelings to CoCT:BMB. 3. River reserves: Grass and plants within 2m of any river or waterway should not be cut at all. Threat 7. Drains & canals Desired Objective: Steep banks of stormwater systems are a major barrier to toads and toadlets. It is imperative in toad foraging areas that stormwater systems allow toads to escape and return to their foraging sites. It is not necessary to redesign or reconfigure systems provided that suitably spaced escape areas are available. These should be spaced at least every 200m. Canals, drains and culverts that potentially redirect toads from one breeding site to another, should be targeted for immediate action to allow toads to escape. Actions Needed:
Inappropriate actions: No further canals should be built or planned for – all stormwater systems should be planned in as natural state as possible. Notes: 1. Canals should have as little hard bottom as possible. Where possible fringing vegetation and riffle stones should be incorporated into canals so as to lower predation and desiccation. Where possible canals should be replaced with contoured natural slopes. Canals should be limited to areas where natural banks are not possible. Any development plan that proposes the canalization piping of a river should be rejected. 2. Toad escape routes can include ladders and steps. These must be able to function as escapes during both high and low flows. Dams, weirs and humps should be incorporated with ladders where ladders cannot function without them. 3. Drains with sumps should be avoided. Grids should be flush to prevent toads from falling in, being trapped or being crushed during peak flows in sunken grids. Deep drains should have a proportion of drains (every 200m) with ladders or steps to allow animals to escape. Threat 8. Culverts, curbstones and pavements Desired Objective: Toads (but not so much toadlets, which can scale walls under moist conditions to over a metre) are severely hampered by obstructions taller than 100mm. These constitute a major barrier that can impede migrations, cause exhaustion, result in increased predation and mortality and channel toads to stormwater drains. They also keep toads on the roads for longer stretches and times than is necessary and thus increase traffic deaths. (They can also profitably be used to maneuver toads to suitable crossing points over roads and obstructions such as canals) Whereas modifications are often trivial (such as placing pipes or steps against curbs, or replacing curbstones with smaller curbstones (less than 50mm tall) or half-round gutters), authorities are reluctant to allow volunteers to interfere with road edges. Thus curbstone modification should exclusively be done by local road authorities. However, these often take inordinately long to get effected, and volunteers are often frustrated by the slow pace of action. Toad-friendly curbs require that barriers such as curbstones should have easy scaleable flagstones every 100-200m. At blackspots and breeding sites these may need to be more frequent, or curbstones should simply be removed and replaced with a toad-friendly alternative. External funding should be raised to get a contractor to install these modifications as and where required. Depending on funding availability areas could be prioritized. CoCT Roads and Stormwater will prefer a plan with a budget. Perhaps a “Toad friendly curb” should be investigated? In most urban and suburban areas, driveways provide adequate breaks in curbstones.
Inappropriate actions: None noted. Threat 9. Eutrophication and Water quality Desired Objective: Western Leopard Toads are quite catholic in their environmental requirements. They tolerate much eutrophication, siltation, invasive weeds both indigenous and alien, and pollutants. However, even they have their limits and waterbodies should be maintained in a state in which Leopard Toads are able to annually breed in them. Actions Needed:
Inappropriate actions: None. Notes:
1. Silvermine wetlands had 10 sewerage spills during 2004-2006 (L. Walter, pers. comm..) due to faulty warning systems on pump systems Threat 10. Swimming pools, ornamental pools, water features and pet waterbowls Desired Objective: Water features with high rims prevent adult toads from escaping. After a few hours of swimming they absorb too much water and die. High levels of chlorine kill them over a shorter time period. The solution is simple. Often merely leaving the weir cover off is sufficient to allow toads to escape. A ladder is required to allow toads to climb out: this can comprise at the simplest level some netting dangling over the pool edge and anchored to the shore, to floating steps and platforms anchored to the side. Alternatively a “beach pool” with gently sloping sides, or a flush pool with water filled to the brim and spilling into side drains (provided theses are toad safe) are acceptable solutions.
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