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Denne rapport er del III af en opdatering af DCEs videnskabelige rapport nr. 52 om ”Vurdering af forstyrrelsestrusler i Natura 2000-områderne”, der blev udgivet i 2013. Rapporten gennemgår med baggrund i de nyeste Natura 2000-basisanalyser og planer (2022-2027) fuglebeskytteelses- og habitatområderne på Øerne, i Sydøstkattegat. Bælthavene og Østersøen. I rapporten vurderes det for hvert område, om en reservatbekendtgørelse er et relevant forvaltningsværktøj i forhold til at sikre de fugle- og pattedyrarter, der indgår i områdernes udpegningsgrundlag, mod forstyrrelser.

Denne rapport er del II af en opdatering af DCEs faglige rapport nr. 52 om ”Vurdering af forstyrrelsestrusler i Natura 2000-områderne”, der blev udgivet i 2013. Rapporten gennemgår med baggrund i de nyeste Natura 2000-basisanalyser og planer (2022-2027) fuglebeskyttelses- og habitatområderne i Jylland, Vesterhavet, Skagerrak, Nord- og Sydvestkattegat. I rapporten vurderes det for hvert område, om en reservatbekendtgørelse er et relevant forvaltningsværktøj i forhold til at sikre de fugle- og pattedyrarter, der indgår i områdernes udpegningsgrundlag, mod forstyrrelser.

Denne rapport er del I af en opdatering af DCEs videnskabelige rapport nr. 52 om ”Vurdering af forstyrrelsestrusler i Natura 2000-områderne”, der blev udgivet i 2013. Rapporten giver en generel introduktion til afrapporteringens formål og metode samt en omfattende litteraturgennemgang i relation til de arter af fugle og pattedyr, der indgår i Natura 2000-områdernes udpegningsgrundlag. Den tilgængelige viden om forskellige menneskelige forstyrrelser, deres effekter og påvirkninger af fugle og pattedyr præsenteres, udviklingen i omfanget af disse beskrives, og der gives nogle praktiske erfaringer omkring håndtering af forstyrrelser. Rapporten giver også noglegenerelle anbefalinger for artsgrupper, hvor forstyrrelsesproblematikken kan udgøre et særligt problem. To efterfølgende rapporter gennemgår Natura 2000-områderne i henholdsvis Jylland og på Øerne, begge med omkringliggende havområder.

Spættet sæl (Phoca vitulina, L.1758) er et havpattedyr,som findes i Nordeuropa og alle danske farvande, men ersjælden omkring Bornholm. Flere steder i dens udbredelsesområdeobserveres spættet sæl i floder og åer, dettegælder også i Danmark. Det er naturligt for spættet sæl atsvømme langt op i større vandløb i deres søgen efter føde.Det har været årsag til konflikter med især lystfiskere, deroplever faldende fangster når sælerne er i åen, og skabtspørgsmål om sælernes effekter på vandløbenes bestandeaf ørred og laks. Gennem indberetninger, interviews,GPS-mærkede sæler samt overvågning af Karup Å, viserdenne rapport at de spættede sæler ind i mellem søgerop i Karup Å-system, men at det formenligt er et begrænsetantal sæler uden nogen væsentlig effekt på åerneshavørredbestand. Generelt lader det til at forekomsten afsæler der søger op i åerne, er højere de år hvor der er etlavt antal optalte sæler på hvilepladserne i den centraledel af Limfjorden. Det kan skyldes at når fødemængden erlav i de centrale bredninger søger sælerne i højere gradop i åerne

An animal’s body condition directly influences its survival and reproductive fitness, and therefore also the health of the populations. Monitoring cetaceans’ morphometric measurements are usually obtained from stranded or bycaught individuals. This may bias interpretations on age - and sex-related growth as well as the status of their populations. The purpose of this study was to determine morphometric measurements of harbour porpoises (Phocoena phocoena) by using overhead video recordings from commercial UAVs (Unmanned Aerial Vehicles). From a customised program that implements the UAV parameters (height, gimbal orientation, camera parameters and Field of View), we were able to obtain the length and girth of 7 individual harbour porpoises of known sizes, very similar to the actual measurements and with a maximum error of 7.4%. Using length and girth, enabled determination of a body condition score (BMI Index) for each animal with an overall average error of 0.8 points. The method was then applied on recordings of free-ranging harbour porpoises with calves to determine the body condition. Furthermore the length was used to predict an approximate age, that all corresponded with the calves being born during spring. This is a very cost-effective monitoring method and a valuable complement to the current body assessment methods from bycaught or stranded animals that can aid in monitoring the growth and health of calves and adults on population scales throughout various seasons. An animal’s body condition directly influences its survival and reproductive fitness, and therefore also the health of the populations. Monitoring cetaceans’ morphometric measurements are usually obtained from stranded or bycaught individuals. This may bias interpretations on age - and sex-related growth as well as the status of their populations. The purpose of this study was to determine morphometric measurements of harbour porpoises (Phocoena phocoena) by using overhead video recordings from commercial UAVs (Unmanned Aerial Vehicles). From a customised program that implements the UAV parameters (height, gimbal orientation, camera parameters and Field of View), we were able to obtain the length and girth of 7 individual harbour porpoises of known sizes, very similar to the actual measurements and with a maximum error of 7.4%. Using length and girth, enabled determination of a body condition score (BMI Index) for each animal with an overall average error of 0.8 points. The method was then applied on recordings of free-ranging harbour porpoises with calves to determine the body condition. Furthermore the length was used to predict an approximate age, that all corresponded with the calves being born during spring. This is a very cost-effective monitoring method and a valuable complement to the current body assessment methods from bycaught or stranded animals that can aid in monitoring the growth and health of calves and adults on population scales throughout various seasons.

Dolphin tourism is a growing industry all over the world. While this may bring economic growth to local communities, it also poses a potential threat to the animals if it is not conducted in a sustainable way. On Zanzibar in Tanzania, the resident Indo-pacific bottlenose dolphins (Tursiops aduncus) and Indian Ocean humpback dolphins (Sousa plumbea) are exposed to a high intensity of tourist activities in the critical areas they use especially for social interactions. The Department of Fisheries and Marine Resources Zanzibar, have issued ten proposed guidelines for dolphin swimming, but they are not enforced, so the behaviour of vessel operators and tourists are not restricted. This study investigated the tourism’s impact on the bottlenose dolphins on Zanzibar. A focal pod sample was used to compare the number of dolphins and their behavioural states and events (tail slap, breach and forced to change behaviour/swimming direction), to the number of boats, tourists (in total and in the water) and their amount of inconsiderate behaviour. The observations were vessel based and completed every 3 min. for a trial period of 30 min. The results suggest that the intensity of tourist activities do affect the number of bottlenose dolphins and their behavioural states and events. The pod size decreased with increasing number of boats. The dolphins’ social, foraging and resting behaviour decreased with the increasing intensity of tourists, while time spend on travelling increased dramatically. The boats and the tourists all tended to force the dolphins to change their behaviour considerably. Dolphin tourism is a growing industry all over the world. While this may bring economic growth to local communities, it also poses a potential threat to the animals if it is not conducted in a sustainable way. On Zanzibar in Tanzania, the resident Indo-pacific bottlenose dolphins (Tursiops aduncus) and Indian Ocean humpback dolphins (Sousa plumbea) are exposed to a high intensity of tourist activities in the critical areas they use especially for social interactions. The Department of Fisheries and Marine Resources Zanzibar, have issued ten proposed guidelines for dolphin swimming, but they are not enforced, so the behaviour of vessel operators and tourists are not restricted. This study investigated the tourism’s impact on the bottlenose dolphins on Zanzibar. A focal pod sample was used to compare the number of dolphins and their behavioural states and events (tail slap, breach and forced to change behaviour/swimming direction), to the number of boats, tourists (in total and in the water) and their amount of inconsiderate behaviour. The observations were vessel based and completed every 3 min. for a trial period of 30 min. The results suggest that the intensity of tourist activities do affect the number of bottlenose dolphins and their behavioural states and events. The pod size decreased with increasing number of boats. The dolphins’ social, foraging and resting behaviour decreased with the increasing intensity of tourists, while time spend on travelling increased dramatically. The boats and the tourists all tended to force the dolphins to change their behaviour considerably.