Floating Pennywort Project. River Medway and River Cray locations

Transcription

1 Floating Pennywort Project River Medway and River Cray locations 2011 Andrea Griffiths (BSc) Partnership Officer Medway Valley Countryside Partnership MVCP Floating Pennywort Report 2011 Andrea Griffiths Partnership Officer 1

2 Contents: 1.0 Introduction Pg River Cray Pg River Medway Pg Interpretation Pg Finance Pg Summary Pg Future Recommendations Pg 15 MVCP Floating Pennywort Report 2011 Andrea Griffiths Partnership Officer 2

3 1.0 Introduction: Medway Valley Countryside Partnership (MVCP) delivers the Giant Hogweed control programme in the Medway Catchment. This project includes the control of all plants (where landowner permission has been granted) across the entire Medway Catchment area; the length of the freshwater section of the Medway and the Medway s main tributaries. In 2011 the River Cray was amalgamated into the project, in order to continue with the work which North West Kent Countryside Partnership (NWKCP) and Thames 21 have carried out in the past. Due to the Giant Hogweed project being catchment wide, covering almost 200km of riparian habitat, it doubles as a biosecurity measure for the catchment as we can observe any other issues or Invasive Non Natives Species (INNS) which require our attention. MVCP also have a large bank of River Warden volunteers who patrol the riversides on a regular basis. Due to the increasing treatment which MVCP have done on additional species, including Floating Pennywort (FPW), Japanese knotweed (JKW) and Himalayan balsam (HB) as well as the ongoing Giant Hogweed (GH) control, the project has slowly become known as the Giant Hogweed and Invasive Non Native Flora control programme. An annual report for the project is written every year but after the completion of this report in 2011 a new issue with Floating Pennywort on the Medway was discovered. This report therefore is in addition to the 2011 Annual Report and details the River Medway control of Floating Pennywort and reiterates on the work done close to the River Cray. MVCP Floating Pennywort Report 2011 Andrea Griffiths Partnership Officer 3

4 2.0 River Cray: The main river is affected by GH and HB. Some parts have an abundance of both plants. GH was treated, in some locations, along the Cray by MVCP in With suitable funding this will be repeated in In 2012 Thames 21 will address some areas of HB with volunteers. Floating Pennywort is not present in the main river or its tributary the River Shuttle, however it has been present in the Sidcup Golf Course ponds for several years. NWKCP were approached by the Golf Course in 2007/08 regarding FPW in their ponds. Following site visits by NWKCP, the London Borough of Bexley (LBB) granted NWKCP some funding to cover the treatment of the plants at that time. The following year a repeat treatment was required but, due to unresolved matters over responsibility, a follow up treatment did not take place. Over concerns for the River Shuttle and subsequently the River Cray, MVCP were requested by LBB to look at this situation again in With Environment Agency funding, specifically for FPW, two treatments of the FPW in this location were carried out and some brief survey work conducted by the contractor (see Figure 1). The treatment was with the herbicide Glyphosate using spray nozzles and administered by MVCP contractor Brian Thomas of FCS Vegetation Care and Control. This was carried out on foot and by boat. Both treatments took place two weeks apart in September MVCP Floating Pennywort Report 2011 Andrea Griffiths Partnership Officer 4

5 Figure 1: Floating Pennywort (and Giant Hogweed) in the River Cray area. (Points for the FPW at the Sidcup ponds are general and do not cover the entire area of the ponds affected. Data on GH was limited in 2011 due to a late amalgamation of the area into the project). MVCP Floating Pennywort Report 2011 Andrea Griffiths Partnership Officer 5

6 3.0 River Medway: There is some historical data for FPW in the area. These small patches have been treated by MVCP in the past and there has been no evidence that these previous patches did not die following treatment. Treatment was successful on the previous small patches. In September 2011 an MVCP River Warden volunteer reported FPW on the River Medway between the disused Stoneham Lock and Little Venice Marina in the Yalding area. Upon receiving this report MVCP surveyed the stretch of the Medway in question. This survey was done on foot from the bank and at that time eight patches of FPW were recorded, as shown in Figure 2. Plate 1 and 2 show some of the initial mats as of September Figure 2: Initial Survey of FPW in the River Medway September 2011 MVCP Floating Pennywort Report 2011 Andrea Griffiths Partnership Officer 6

7 Plate 1: FPW between Stoneham Lock and Yalding. September 2011 Andrea Griffiths MVCP Plate 2: FPW between Stoneham Lock and Yalding. September 2011 Andrea Griffiths MVCP MVCP Floating Pennywort Report 2011 Andrea Griffiths Partnership Officer 7

8 Due to this unusual outbreak of FPW in the Medway, the Environment Agency were approached and funding to chemically treat these plants (and to fund the work carried out at Sidcup Golf Course See River Cray) was obtained. Confirmation of the funding was given approximately a month after the September survey and treatment of the FPW was scheduled for the first week in November. It was vital to understand where the source of this infestation originated. No FPW had been reported above Stoneham Lock and as such MVCP staff surveyed Tudeley Brook, a small tributary of the Medway which enters the Medway just above Stoneham Lock. This survey was undertaken of the lower 4 miles (approx) of Tudeley Brook (Figure 3) including the section of land through J Clubb Quarry (where FPW had been seen in the past and treated by MVCP contractors). Figure 3: Location of Tudeley Brook Survey 1 st November 2011 (Red arrows represent the Tudeley Brook Survey, Black arrows the East Peckham Survey) MVCP Floating Pennywort Report 2011 Andrea Griffiths Partnership Officer 8

9 No FPW was seen at the Quarry or anywhere along Tudeley Brook during this survey. The stream which flows behind East Peckham was also surveyed on Monday 7 th November, no FPW was observed. The first treatment of the FPW was undertaken on Wednesday 2 nd November. This was a method using Glyphosate using hand held spray nozzles. It was carried out both on foot (in areas such as Yalding Fen) and in a boat. Compared to the first survey in September, at the time of treatment a much greater degree of abundance was noted. This is both due to better observation from the boat allowing for greater data capture and also due to the spread of the FPW in the month between first detection and treatment. On 2 nd November 2011, 80 individual FPW mats were recorded between Stoneham Lock and Little Venice Marina and Hampstead Marina. FPW was observed in numerous places and in a variety of mat sizes. It had spread into the channels leading into Yalding Fen and had also begun to move upstream into the lower stretches of the River Beult SSSI, the confluence of which is at Yalding. In comparison to Figure 2, Figure 4 shows the actual abundance of FPW on the River Medway in November This map highlights both the locations of each individual mat of FPW and the size of that mat in M 2. The red pointer at the bottom of the map is the source pond at Medway View. The point does not show the full extend of the problem in this pond. As would be expected where the river meanders larger mats were observed. The map also shows the abundance of smaller patches which were becoming established due to breaking off the larger mats and drifting downstream. MVCP Floating Pennywort Report 2011 Andrea Griffiths Partnership Officer 9

10 Figure 4: Actual FPW locations and mat sizes in November 2011 approximately 6 weeks after the first observations. (The extent of the FPW at Yalding Fen is not represented on this map) On 2 nd November, all the observed mats of FPW were treated and the source of the FPW was identified. The source appears to be a pond belonging to land known as Medway View (red pointer at the bottom of the map in Figure 4). The pond on site borders the River Medway closely and infected water from the pond had seeped into the Medway carrying the FPW plants into the main river. The map of this source pond can be seen in Figure 5: MVCP Floating Pennywort Report 2011 Andrea Griffiths Partnership Officer 10

11 Figure 5: Map showing location of FPW source pond A second treatment was scheduled both to treat the source pond and to survey the Medway lower down stream and ensure the first treatment was successful. This was scheduled for and carried out on 17 th November. On the 17 th November approximately 85 additional stems of FPW were extracted from the water manually from the boat. This was during the additional survey of the River Medway from Yalding to Wateringbury. These 85 stems had broken off the original mats and floated downstream, all observed were extracted. Also on the 17 th November the source pond was treated. This pond measures approximately 2300m 2. Approximately 75% of this pond was affected by FPW. As such an area of approximately 1725m 2 was affected by FPW in the source pond, as shown in Plates 3 and 4. MVCP Floating Pennywort Report 2011 Andrea Griffiths Partnership Officer 11

12 Plate 3: FPW in source pond November 2011 Brian Thomas FCS Vegetation Care and Control Plate 4: FPW in source pond November 2011 Brian Thomas FCS Vegetation Care and Control MVCP Floating Pennywort Report 2011 Andrea Griffiths Partnership Officer 12

13 3.1 Interpretation: In addition to surveying and treatment, information posters (Plate 5 below) were produced by MVCP and displayed by the Environment Agency around locks. This same information poster was also included in the Yalding Parish Council magazine and on their website and was distributed via the Medway River Users Association (MURA). The aim of the poster was both to inform members of the local community and the boating fraternity that Floating Pennywort had been observed and was being treated by MVCP. It was also to prompt any additional observations of FPW at the time of the project and in the future, to be reported to MVCP without delay. Plate 5: FPW Information Poster for the River Medway produced by MVCP Andrea Griffiths MVCP MVCP Floating Pennywort Report 2011 Andrea Griffiths Partnership Officer 13

14 4.0 Financial Information: Table 1: Information on income and costs for the FPW specific invasive species project in Income/Funding Environment Agency FPW Funding 1, Additional Match from MVCP s INNS project for 1, additional staff time = Total Income for FPW Project 2011 = 2, Costs Chemical Treatment and Contractor time for River Cray / Sidcup Golf Course Ponds Chemical Treatment and Contractor time for 1, River Medway and source pond MVCP staff time on FPW project inc 1, administration, project management, surveying and data capture = approx 60 hours Total Costs for FPW Project 2011 = 2, Due to an increase in the abundance and distribution of the FPW in the River Medway from the initial survey to the final survey and treatment time in November, costs considerably increased from that originally estimated and funded. MVCP staff time increased due to locating the landowner of the source pond, due to creating and distributing interpretation and due to the amplified project size. For this reason the project would ve worked at a slight loss but MVCP also manage the Giant Hogweed and Invasive Non Native Species Control Programme and as such some funds for MVCP staff time were matched from this main project to cover staff time costs on this project. This highlights the baseline figure required for additional surveying and treatment in MVCP Floating Pennywort Report 2011 Andrea Griffiths Partnership Officer 14

15 5.0 Summary: The FPW spread rapidly in the short period between initial observations and treatment time (as seen in Figures 2 and then 4). Approximately 4.4km of the River Medway was affected by FPW mats by November. Over 80 mats were observed and treated in this stretch of the Medway. Over 85 additional individual stems of FPW were collected from the River Medway between Yalding and Wateringbury another 5km of the River In addition 7.5km of Tudeley Brook was surveyed to ensure no FPW was present in the Brook. The source of the FPW problem was located. The landowner informed and the source treated. Over 1725m 2 of FPW approximately was treated in the source pond. All locations and mat sizes were logged on GIS Interpretation posters were produced and circulated locally. 5.0 Recommendations: Although a thorough chemical application was applied to all of the observable FPW mats and plants, it is feasible to suggest that some FPW may survive in the source pond given the extent of the problem in this location. Additional surveying and possible treatment will be required in 2012 to ensure the ongoing security of the River Medway. In addition in 2011 the E.A has agreed to install a barrier between the source pond and the River Medway channel to assist the project in stopping any fragments of FPW or any live stems from drifting into the main channel. Additional funding will be required for surveying the effected area again in 2012 and to carrying out any treatment if required. This project highlighted the speed at which this invasive species can spread and that funds need to be available for another rapid response. MVCP Floating Pennywort Report 2011 Andrea Griffiths Partnership Officer 15

16 Andrea Griffiths (BSc Hons) Partnership Officer Medway Valley Countryside Partnership 3 Lock Cottages Lock Lane Sandling Kent ME14 3AU andrea.griffiths@kent.gov.uk MVCP Floating Pennywort Report 2011 Andrea Griffiths Partnership Officer 16