Looe Island Seal Photo Identification Project 2008/9 (LISPIP) : Feb 2010

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1 Identifying and monitoring Looe seals Looe Island Seal Photo Identification Project 2008/9 (LISPIP) : Feb 2010 LISPIP is a collaborative project between the Looe VMCA Marine Volunteers, Cornwall Wildlife Trust and Cornwall Seal Group, which aims to discover the following information:- The sites used by seals in the sea and on land The seasonality of any seal sites The number of seals visiting the sites Information about the seals ages, sex as well as information about their nutritional and health status Links to other seal sites in Cornwall made by individual seals, using photo identification techniques. This information will provide a more informed basis upon which conservation decisions can be made. February 2010 : Method On 17 th February 2009, 13 surveyors (Abby, Alan, Cheryl, Chris, Christine, Derek, Emma, Kate, Katie, Kym, Matt, Nicola and Sue) were ferried over to St George s Island on the CWT boat by Tim, leaving Looe harbour around 9.30am and returning just before 5pm. The following activities were carried out:- A planning meeting to organise the day s activities A walk around the island to:- o Orientate surveyors o To identify survey sites o Familiarise new observers with the recording protocol (new surveyors paired with experienced ones) o Carry out a bird count A 2 1 / 2 hour survey period from approximately 1 hour before low tide to 1 hour and 30 mins after low tide A data collection discussion and analysis Seal survey sites Site 1 : Main Beach Site 2 : Jetty Beach Site 3 : Little Island East* Site 4 : Inner Ranneys Bay Site 5 : Outer Ranneys Site 6 : Lower Bench Site 7 : White Rock *(Only accessible outside the bird breeding season) 1/9

2 As a result of the pilot survey and our first familiarisation walk around the island, the following decisions were made about the LISPIP Survey Protocol:- To conduct monthly seal surveys during 2009, weather and sea conditions permitting Surveys to be undertaken within a window of 2 hours either side of low tide Surveyors to work in paired teams or trios (mixing new and experienced observers where appropriate) One surveyor to remain at sites 3, 4 and 5 to take digiscoped images of seals present, to maximise photo ID potential Survey teams to rotate clockwise around the survey sites Survey teams to begin walking to the next site at agreed half hour intervals During each survey period, the following data to be recorded:- o The maximum number of seals to be counted in and out of the water o Seals to be classified as adult male, adult female, juvenile male or female (up to 4 years old), weaner (under 1 year old), white coat pup (under 3 weeks) or unknown o Seal behaviour using a detailed ethogram o Evidence of net entanglement, marine debris and disturbance o Environment conditions Human/seal interaction is noted, including feeding, marine litter, net entanglement & disturbance Disturbance to be minimised by:- o Land based surveyors remaining quiet and still when being looked at by seals and keeping below the horizon if close to seals on land. o A quiet & slow boat approach. At the first signs of disturbance, a still silence to be maintained by surveyors and the boat to back away if signs of seal stress continue. Side view photos of the seals necks/bodies to be taken using digital cameras with optical zoom lenses with optical image stabilisers or by digiscoping. CSG has loaned the Looe VMCA volunteers a digital camera to take shots of seals seen between surveys. Contemporaneous collation of sightings data in a time/location chart and discussion of likely overlap in sightings using mapped location, sex/age and behaviour data. Anecdontal seal sightings outside of seal survey to be recorded, as appropriate. Seal sightings by Wardens Claire and Jon to be recorded between surveys using separate form. A count of the birds present will be recorded during a single, complete circumnavigation of the island. February 2010 : Results 7 seal sites were surveyed from 5 different locations by survey teams of 2 or 3 people, whilst Sue remained at site 5 to take digital digiscoped images of the seals on the Ranneys. At sites 3, 4 & 5, where possible, the survey team separated, with one person surveying nearer to Little Island, survey site 3 & the other person standing on cliffs west of Little Island. Initial survey teams for each site were:- Site 1 : Main Beach : Katie, Matt & Nicola Site 2 : Jetty Beach : Christine & Derek Site 3 : Little Island East : Kate, Kym & Sue Site 4 : Inner Ranneys Bay : Kate, Kym & Sue Site 5 : Outer Ranneys : Kate, Kym & Sue Site 6 : Lower Bench : Alan & Chris Site 7 : White Rock : Abby, Cheryl & Emma Date Survey start Survey end Time of low water Wind direction 17/02/ pm 15.00pm S 2/9

3 Number of seals observed and environmental conditions (*Thought to be the same seal moving between sites) Site Total to to to to Site Max Behaviours WB, WDR, WDR, WDR, WDR, WDR Wind force ST BR/W W/BR/W W BR Weather Overcast, sunny spells / Drizzle / Rain Debris 1 Plastic cups Red cloth Net Rubber disk 2 Plastic containers Cans 1 Wood 0 2 Green trawl net and fishing floats 3/9

4 Two seals were seen during the first recording session by observers at sites 3, 4 and 5 and from site 6. Both these seals were in the sea at site 5. One seal remained in the same location for the whole survey. Behaviour recordings : (Please see the end of this section for behaviour code descriptions.) WT WD WP WF WS WE WDA WDR WB WL WIB HA HR HM HTr HTh HF WH HW The seals displayed 2 different behaviours during the seal survey. The most observed seal behaviour was Water diving rest. This behaviour was displayed repeatedly by LF1 Snowdrop in the small bay on the NW side of the Outer Ranneys. 4/9

5 February 2010 : Discussion Seals were only observed at one of the sites during the survey period site 5, the outer Ranneys. Here there were 2 adult seals in the sea an adult female LF1 Snowdrop and a seal of unknown age/sex. Seal identification One of the seals at site 5 was identified in the field using the new photo ID cards. The female s pattern was clearly identified from both sides as being LF1 Snowdrop, who has now been identified 6 times. On the 15 th February, Claire took photos of another adult female seal at site 4, who was identified from both sides before the survey as LF3 Duchess, who has been identified a total of 5 times. Excellent photos of an unknown adult male were taken by Claire on 06/02/10, which could have been Barry, but the identification cannot be confirmed. LF1 Snowdrop 5/9

6 LF3 Duchess 15/02/10 : Site 4 15/02/10 : Site 4 ID file photo 15/02/10 : Site 4 ID file photo ID file photo Unknown male photographed by Claire on 06/02/10 LM 4 Barry : ID shot Unidentified adult male Possibly Barry? 6/9

7 Identification summary:- LF1 is LF2 LF3 LM4 LMF6 LF8 LM9 LMF10 LM11 LF12 LMF13 LF15 LM16 L17 Snowdrop Duchess Barry Paw print Lucille Sunrise Wotsit Gus Lightning Nemo Dame Etna Arrow Juvie 30/05/08 15/03/09 29/08/08 26/05/09 26/05/09 21/08/09 21/08/09 21/08/09 21/08/09 21/08/09 07/09/09 07/09/09 07/09/09 14/02/09 26/05/09 10/06/09 24/08/09 24/08/09 26/05/09 24/08/09 14/06/09 07/09/09 26/07/09 01/10/09 26/07/09 08/10/09 21/08/09 15/02/10 24/08/09 17/02/10 07/09/09 12/10/09 Seal disturbance Whilst up to 3 war ships could be seen on the horizon to the south of the Ranneys, no other boats were observed and no seals were disturbed before, during or after the survey. Age and sex of observed seals The maximum number of seals observed at all the sites around the island during a single half hour survey period at all sites was 2 (recorded during 1 out of the 5 survey periods) Of these 2 seals seen, 1 was an adult female and the other was of unknown age/sex. Interaction with boats and feeding of seals by humans: No boats were present. Marine debris : Marine debris was recorded at sites 1, 2, 5 and 7 including net, a rubber disk 0.5m in diameter, red cloth, plastic cups, cans, wood and a long line of green trawl netting. A large pile of marine debris has already been cleared up by Claire and Jon and awaits collection on the ramp at site 1. Net entanglement :No net entangled seals were observed. Seasonal distribution of seals observed : The maximum number of seals observed during this survey appears to have stabilised at a lower level for the winter. This is only the second repeat survey month both December and February demonstrating a degree of inter annual variation, particularly in February, as 6 seals were seen at this time last year. 7/9

8 Warden s sightings : The seasonal wardens have recently returned to St George s Island and begun their seal recordings for 2010, of which a total of 11 records exist. Most seals observed by Claire were seen at site 5, the Outer Ranneys, although seals were additionally seen at sites 2 and 4 (the most noteable of which was LF3 Duchess!) 8/9

9 The most frequently observed number of seals seen by Claire was 1. Many thanks to everyone who took part in this seal survey. Surveyors volunteer their time and paid a 5 contribution each to the cost of the boat crossing with the remaining cost being met by Cornwall Wildlife Trust. Thanks too to Claire, whose records taken between LISPIP surveys greatly adds to our understanding of seal activity at this location. Thanks to Abby Crosby for organising this seal survey. In future, it was agreed that Katie, Matt and Nicola will organise the surveys in collaboration with Claire. Sue Sayer Cornwall Seal Group sue@cornwallsealgroup.co.uk : 9/9