Progress report on aerial surveys of seals at Rødsand seal sanctuary and adjacent seal haulout sites during January-July 2004

Transcription

1 Progress report on aerial surveys of seals at Rødsand seal sanctuary and adjacent seal haulout sites during January-y 24 Technical report to Energi E2 A/S Jonas Teilmann, Rune Dietz, Susi Manuela Clermont Edrén National Environmental Research Institute (NERI) Department of Arctic Environment Ministry of the Environment Denmark August 24

2 Contents 1 Summary 3 2 Introduction 3 3 Materials and methods 4 4 Results 5 5 References 8 6 Appendix

3 1 Summary As requested by Energy E2 A/S, this short progress report on data collected during aerial surveys of the Rødsand seal sanctuary and adjacent haulout sites during the first half of 24. Data from previous surveys are also shown for comparison with 24 results. Analyses of data are still incomplete and await completion at the end of the year. The purpose of this progress report is thus solely to make the collected raw data available to Energy E2 A/S. Final analysis and conclusions will be reported in the 24 annual report for the project. 2 Introduction In connection to the construction and operation of Nysted Offshore Wind Farm (completed in November 23), several biological monitoring programs were set up. The present program deals with possible effects of the wind farm on seals hauling out in the vicinity of the wind farm. The effects on seals during the construction period has been described previously (Teilmann et al. 24). The ongoing program focus on the effect of the operation of the wind farm, i.e. assessing possible shift in haulout sites in the area. Methodology of the 24 program closely follow what has been described previously (Teilmann et al. 24). Rødsand seal sanctuary is a part of seal management area 4 (Fig. 2, Teilmann & Heide-Jørgensen 21). This area is believed to consist of a closed population of harbour seals with little exchange to other areas. A possible reaction to disturbance from the construction of the wind farm may be that the seals may use other haulout sites to a higher extend. Therefore monthly aerial surveys of all seal localities in area 4 have been carried out since spring 22. In addition aerial surveys in August have been conducted since 199 as part of the national seal survey program and these surveys will serve as part of the baseline data. Based on the number of seals on land, Rødsand is considered the most important haulout and breeding site for harbour seals in the southwestern Baltic Sea (Teilmann & Heide-Jørgensen 21). From satellite tracking of harbour and grey seals at Rødsand (Dietz et al. 23), we saw that both species used several other haulout sites. They frequently visited Vitten (about 1 km west of the seal sanctuary) and Flintehorne Odde (about 5 km north of the sanctuary). Grey seals also visited seal localities in Bøgestrømmen, at Saltholm, and Falsterbo in the western Baltic as well as several sites along the Swedish East Coast and Estonia in the central Baltic. 3

4 3 Materials and methods Seal locations in management area 4 Sound Saltholm Great Belt Sjælland Dyrefod Aunø Fjord Møn Falsterbo/ Mårkläppan Bøgestrømmen Vitten/ Skrollen Lolland Falster Flintehorne Odde Rødsand Western Baltic Fehmarn Figure 1. Map of management area 4 (Southwestern Baltic) with area names and seal sites. Seal haulout sites are indicated with arrows. Since 199, the same flight type (Cessna 172), pilots and observers have been used to count seals in the area since 199 (Teilmann & Heide- Jørgensen 21). These surveys have been conducted in the Danish Baltic (management area 4, Fig. 1) every year, or every second year, three times during the moult in late August. Both counts made during the flight and photos of larger seal groups for later examination are done. The region consists of the seal sites at Rødsand, Vitten, Flintehorne Odde, Aunø Fjord, Dyrefod, Bøgestrømmen, Saltholm, and Falsterbo (Fig. 2). These sites are considered to host parts of the same stock of harbour seals, which means that there may be regular movements between these sites. The monthly aerial surveys for the wind farm monitoring program started in March 22 and continued until August 22. The surveys were resumed in ruary 23. This progress report provides data on the monthly surveys from January to y 23. 4

5 4 Results On Rødsand no harbour seals were observed in March 22 and ruary, March, October, December 23, and ruary, March 24. This is in accordance with the video camera observations that very few seals are observed at Rødsand during winter, early spring and late autumn (Edrén et al. 24). The number of seals peak in August-tember. The same general pattern is seen at Falsterbo, Aunø, and Bøgestrømmen, while Saltholm and Vitten/Skrollen show a more variable pattern with relatively more seals during spring (Fig. 4). This could mean that seals are moving between sites at certain time of the year to utilise better food resources or more undisturbed or protected haulout sites. Rødsand and Vitten/Skrollen are the two seal sites closest to the wind farm. At Vitten/Skrollen the number of seals observed was generally higher in 23 during the construction (mean=24 seals) of the wind farm than during the baseline (mean=4 seals) in 22 and in the first months of 24 (mean=14). At Rødsand more harbour and grey seals have been observed in il-y 24 (mean=68 harbour/1 grey seals) during operation of the wind farm than during the baseline (mean=29/7 seals) and construction (mean=3/4 seals) phases in the same months. These preliminary results suggest that the seals move between these two localities and that no obvious negative effect from the operation of the wind farm is seen. However, conclusions on the effect of the operating wind farm awaits further data collection and data analysis in the coming annual reports. 5

6 Rødsand Number of seals on land Harbour seals Grey seals Mar 22 Early Aug Mar 23 Oct Dec Early Jan 24 Late Jan Mar Early Late Month Vitten/Skrollen Number of seals on land Harbour seals Mar 22 Early Aug Mar 23 Oct Dec Early Jan 24 Late Jan Mar Early Late Month Falsterbo Number of seals on land Harbour seals Grey seals Mar 22 Early Aug Mar 23 Oct Dec Early Jan 24 Late Jan Mar Early Late 6

7 Saltholm Number of seals on land Harbour seals Mar 22 Early Aug Mar 23 Oct Dec Early Jan 24 Late Jan Mar Early Late Month Avnø Number of seals on land Harbour seals Mar 22 Early Aug Mar 23 Oct Dec Early Jan 24 Late Jan Mar Early Late Month Number of seals on land Bøgestrømmen Harbour seals Mar 22 Early Aug Mar 23 Oct Dec Early Jan 24 Late Jan Mar Early Late Figure 2. Survey results for monthly surveys in southwestern Baltic (management area 4) from March 22 to y 24. Note that no correction factor is applied and that no surveys were conducted from October-December 23 due to a pause in the environment studies for Nysted Offshore Wind Farm. In addition to the monthly surveys, the areas were surveyed three times in late August as part of the national seal monitoring program (Edrén et al. in prep.). 7

8 5 References Dietz, R., J. Teilmann, O.D. Henriksen & K. Laidre 23. Movements of seals from Rødsand seal sanctuary monitored by satellite telemetry. Relative importance of the Nysted Offshore Wind Farm area to the seals. National Environmental Research Institute Technical Report No. 429: 44 pp. rapporter/fr429.pdf Edrén, S.M.C., Teilmann, J., Dietz, R. & Carstensen, J. 24: Effect from the construction of Nysted Offshore Wind Farm on seals in Rødsand seal sanctuary based on remote video monitoring. Report request. Commissioned by ENERGI E2 A/S. National Environmental Research Institute. 31 pp. Available at: Teilmann, J. & M.P. Heide-Jørgensen 21. Tællinger af spættet sæl og gråsæl 2, Østersøen, Kattegat og Limfjorden. In: Laursen, K. Overvågning af fugle og sæler Danmarks Miljøundersgelser. Teilmann, J., Carstensen, J., Dietz, R. & Edrén, S.M.C. 24: Effects on seals at Rødsand seal sanctuary from the construction of Nysted Offshore Wind Farm based on aerial surveys. Report request. Commissioned by EN- ERGI E2 A/S. National Environmental Research Institute. 32 pp.available at: 8

9 6 Appendix 1. Details on surveys conducted in management area 4/Southwestern Baltic from il 23 to January 24 is shown below. Previous observations are presented in Teilmann et al. 23. Aerial survey of seals in Western Baltic Date: Take off: 9:25 Landed: 11:4 Aircraft type: Cessna 172 Pilot: Jens Larsen Speed over locations (knob): Observer front seat 7-8 Rune Dietz Hight over lokations (feet): Observer back seat 4-5 Ida Eskesen Wind, m/s: Cloud cover (1/8) 2-3 m/s /8 Wind direction: Temperatur C : N 1-8 Locality Time Camera1 Camera2 Total Disturbance (%) survey Visuelle observation during (Harbour/g (Harbour/ (harbour/ rey) grey) grey) Susi Rune Aunø 9: Isdække om Dyrefod 9: Falster NW 9: Lolland NØ 9: Flintehorne Odde 1: Vitten/Skrollen 1: i vandet 1/ Rødsand 1: i vandet 3/ Bøgestrøm 1: Kun 1 sten synlig gshoved N 1: Falsterbo Is i lagoonen 8 i 11: vandet 8/ 2 pers. gik tur på stranden v Saltholm 11:2 - - spidsen. 1 sæl i vandet 1/ Amager SØ 11: Total in area 4: Western Baltic harbour seals total: 13 Western Baltic grey seals total: Ingen billeder!!! Camera 1 (Front seat): Nikon F9 Film: Camera 2 (back seat): Nikon D1 Film: 9

10 Aerial survey of seals in Western Baltic Date: Take off: 9:8 Landed: 11:58 Aircraft type: Cessna 172 Pilot: Jens Larsen Speed over locations (knob): Observer front seat 7-8 Susi Edrén Hight over lokations (feet): Observer back seat 4-5 Maja Kirkegaard Wind, m/s: Cloud cover (1/8) ½ 1/8 Wind direction: Temperatur C : 16-2 Locality Time Camera1 Camera2 Total Disturbance (%) survey Visuelle observation during (Harbour/g (Harbour/ (harbour/ rey) grey) grey) Aunø 9: Dyrefod 9: Ekstrem lavvandet - mange sten synlige 39/ Falster NW 9: Lolland NØ 9: Lavvandet, mange sten 15/ Flintehorne Odde 1: sæl på sten ml. Vitten og Vitten/Skrollen 1:8 - - Flintehorne Odde 7/ Rødsand 1: gråsæl i vandet /1 Bøgestrøm 1: / gshoved N 1: Falsterbo 11: i vandet (grå/spættet?) 1/ Stor gruppe på sten øst for Saltholm 11: Saltholm åp 12 sæler 29/ Amager SØ 11: Total in area 4: Western Baltic harbour seals total: 19 Western Baltic grey seals total: 1 Camera 1 (Front seat): Film: Camera 2 (back seat): Film: 1

11 Aerial survey of seals in Western Baltic Date: Take off: 9:15 Landed: 12:15 Aircraft type: Cessna 172 Pilot: Jens Larsen Speed over locations (knob): Observer front seat 9-1 Susi Edrén Hight over lokations (feet): Observer back seat 5 Jonas Teilmann Wind, m/s: Cloud cover (1/8) 4 /8 Wind direction: Temperatur C : Vest 12 Locality Time Camera1 Camera2 Total Disturbance (%) survey Visuelle observation during (Harbour/g (Harbour/ (harbour/ rey) grey) grey) Aunø - For mange lave skyer - Dyrefod 9: på sten, 1 i vandet 13/ Falster NW For mange lave skyer - Lolland NØ 9: på spredte sten 5/ Flintehorne Odde 1:5 - - For mange lave skyer - Vitten/Skrollen 1:3 - - Rødsand 1: sæler på land Bøgestrøm 1: på sten 12/ gshoved N 11: - - Falsterbo 11:2 9 44/16 - ca. 35 spættede og 2 grå 44/16 Saltholm 11: på sten 26 54/ Amager SØ 12: på sten 2 i vandet 6/ Total in area 4: Western Baltic harbour seals total: 134 Western Baltic grey seals total: 16 Camera 1 (Front seat): Nikon D3 Film: Digital Camera 2 (back seat): Nikon F9 Film: Dias Fujichrome 4 11

12 Aerial survey of seals in Western Baltic Date: Take off: 9:15 Landed: 11:4 Aircraft type: Cessna 172 Pilot: Jens Larsen Speed over locations (knob): Observer front seat 7-8 Rune Dietz Hight over lokations (feet): Observer back seat 4-5 Jonas Teilmann Wind, m/s: Cloud cover (1/8) 7- /8 Wind direction: Temperatur C : Øst 8-dec Locality Time Camera1 Camera2 Total Disturbance (%) survey Visuelle observation during (Harbour/g (Harbour/ (harbour/ rey) grey) grey) Susi Rune Aunø 9: Højvande Dyrefod 9: Højvande Falster NW 9: Højvande Lolland NØ 9: Højvande Flintehorne Odde 1: Vitten/Skrollen 1: Rødsand 1:2 79/ Ca. 7 spættede? + 2 i vandet 79/ Bøgestrøm 1: gshoved N 1: Falsterbo 11:1 1 1/97 Ca i vandet - GRÅ? 1/97 Saltholm 11: Amager SØ Måtte ikke flyve den vej Total in area 4: Western Baltic harbour seals total: 8 Western Baltic grey seals total: 97 Camera 1 (Front seat): Nikon D1 Film: Digital Camera 2 (back seat): Nikon F9 Film: Kodachorme 2 12

13 Aerial survey of seals in Western Baltic Date: Take off: 8:3 Landed: 11:29 Aircraft type: Cessna 172 Pilot: Jens Larsen Speed over locations (knob): Observer front seat 7-8 Signe Maj Hight over lokations (feet): Observer back seat 4-5 Susi Edrén Wind, m/s: Cloud cover (1/8) 2-3 /8 Wind direction: Temperatur C : 9 15 Locality Time Camera1 Camera2 Total Disturbance (%) survey Visuelle observation during (Harbour/g (Harbour/ (harbour/ rey) grey) grey) Susi Rune Aunø 8: / Dyrefod 9: i vandet 1/ Falster NW 9: på sten 8/ Lolland NØ 9: på sten, 3 i vandet 15/ Flintehorne Odde 9: Vitten/Skrollen 9:28 1-3/ >3 3/ Rødsand 9:45-75/12 Ca. 7 75/12 Bøgestrøm 1: på sten 17/ gshoved N 1: Falsterbo 1:45-6/95 16 i vandet (4 grupper) 6/111 Saltholm 1: / Amager SØ 11: Total in area 4: Western Baltic harbour seals total: 272 Western Baltic grey seals total: 123 Camera 1 (Front seat): Film: Camera 2 (back seat): Nikon D1 Film: Digital 13

14 Aerial survey of seals in Western Baltic Date: Take off: 9:16 Landed: 12: Aircraft type: Cessna 172 Pilot: Jens Larsen Speed over locations (knob): Observer front seat 7-8 Susi Edrén Hight over lokations (feet): Observer back seat 4-5 Mary Susan Wisz Wind, m/s: Cloud cover (1/8) 6,5 1-2/8 Wind direction: Temperatur C : Locality Time Camera1 Camera2 Total Disturbance (%) survey Visuelle observation during (Harbour/g (Harbour/ (harbour/ rey) grey) grey) Susi Mary Aunø 9: / 62/ 62/ Dyrefod 9: Falster NW 9: Lolland NØ 1: Højvande - inden synlige sten Flintehorne Odde 1: / 3/ 45/ Vitten/Skrollen 1: grå og 1 spæt grupper Rødsand 1:26 59/12 2 sæler i vandet 61/12 Bøgestrøm 1: / 6/ 1/ gshoved N 1: Falsterbo 11:15 18/ 5 i vandet uden for lagoonen 18/5 Saltholm 11: Højvande 8/ Amager SØ Total in area 4: Western Baltic harbour seals total: 294 Western Baltic grey seals total: 62 Camera 1 (Front seat): Nikon D1 Film: Digital Camera 2 (back seat): Nikon F9 Film: Fujichrome Provia 4 14

15 Aerial survey of seals in Western Baltic Date: Take off: 9:3 Landed: 12:15 Aircraft type: Cessna 172 Pilot: Jens Larsen Speed over locations (knob): Observer front seat 7-8 Susi Edrén Hight over lokations (feet): Observer back seat 4-5 Rune Dietz Wind, m/s: Cloud cover (1/8) 2-3 1/8 Wind direction: Temperatur C : 3 17 Locality Time Camera1 Camera2 Total Disturbance (%) survey Visuelle observation during (Harbour/g (Harbour/ (harbour/ rey) grey) grey) Susi Rune Aunø 9: / 117/ 117/ Dyrefod 1:8 - - Falster NW 1: / 15/ 15/ Lolland NØ 1: / 2/ 2/ Flintehorne Odde 1: / 1/ 1/ Vitten/Skrollen 1:32 < / 27/ 27/ Rødsand 1:46 49/16 (én i vand) 1 i vandet 58/16 Bøgestrøm 11: / 14/ 14/ gshoved N 11: / Falsterbo 11:33 61/ 16 i vandet, svært at se art 61/16 Saltholm 11: / 35/ 35/ Amager SØ Total in area 4: Western Baltic harbour seals total: 33 Western Baltic grey seals total: 32 Camera 1 (Front seat): Nikon F9 Film: Fujichrome Provia 4 asa Camera 2 (back seat): Nikon D1 Film: Digital 15