{"id":102,"date":"2011-10-24T10:25:34","date_gmt":"2011-10-24T10:25:34","guid":{"rendered":"http:\/\/wsa.seagrassonline.org\/blog\/?p=102"},"modified":"2012-01-19T15:23:58","modified_gmt":"2012-01-19T15:23:58","slug":"notes-from-the-field-derawan-island-indonesia-2","status":"publish","type":"post","link":"https:\/\/wsa.seagrassonline.org\/blog\/archives\/102","title":{"rendered":"Notes from the Field: Derawan Island, Indonesia"},"content":{"rendered":"
Every fortnight we feature a seagrass meadow from around the world. This week, Marjolijn Christianen shares her experiences working in the beautiful tropical island of Derawan in Indonesia. Marjolijn is currently a PhD student at Radboud University in The Netherlands. She has a blog<\/a> detailing her experiences working with turtles and seagrass.<\/strong><\/em><\/strong><\/em><\/h5>\n
——————————-<\/strong><\/em><\/h5>\n

by Marjolijn Christianen
\n<\/strong><\/em><\/p>\n

The Derawan Archipelago, is a hotspot of biodiversity and located in front of the Berau River on the mainland of East Kalimantan, Indonesia. In recent\u00a0decades the once pristine rainforest and mangroves have been quickly transformed into palm oil\u00a0plantations,\u00a0coal\u00a0mines and\u00a0shrimp\u00a0farms.\u00a0Since\u00a0all this activity\u00a0is concentrated\u00a0around\u00a0the rivers\u00a0it expected that the adjacent\u00a0estuary\u00a0will experience\u00a0great\u00a0effects of the increasing sediment and nutrient loads that will negatively affect the marine life & biodiversity of the adjacent estuary. So what is the effect of this on the seagrasses here?<\/p>\n

\"\"<\/a>

(a) Map of the a Indo-Pacific Ocean with (b) The Derawan Archipelago and the (c) location of the exclosures on Derawan Island (d) Leaves are intensively grazed by green turtles, and a detritus layer is absent.<\/p><\/div>\n

Following a pilot expedition of a Dutch group of marine biologists in 2003, we started with a 5 year PhD project in cooperation with the Indonesian Institute of Sciences (LIPI) and based ourselves on the small & beautiful Island of Derawan. The island is surrounded by a large shallow area (light-blue in picture c above) which is dominated by a mono species Halodule univervis <\/em>meadow. On the other islands of the archipelago you can also find other species like Cymodocea rotundata, Cymodocea serrulata, Halophyla ovalis<\/em> (with very rare dugong tracks), Enhalus acoroides, Thalassia hemprichii, Syringodium isoetifolium.<\/em><\/p>\n

We found that the effect of increasing nutrient loads proved to be much less than the effect of the local grazers. Directly after arrival I was amazed by the extremely shortly grazed leaved, that were also very thin. It just looks like there is someone mowing the underwater seagrass lawns every day. And the extremely high densities of green turtles (Chelonia mydas<\/em>) were found responsible for this. In our latest paper (Christianen et al. 2011, Journal of Ecology, link http:\/\/onlinelibrary.wiley.com\/doi\/10.1111\/j.1365-2745.2011.01900.x\/citedby<\/a>) we estimated that these hungry grazers graze 100% of the daily primairy production of the seagrass meadow.While populations of green turtle have dramatically declined at most other places, green turtle hotspots like Derawan could teach us about the historical role of the role of these megaherbivores. The green turtle not only drives structure and functioning of their foraging ground but also increases the tolerance of seagrass ecosystems to eutrophication (Christianen et al. 2011).<\/p>\n

\"\"<\/a>

It is not difficult to spot green turtles grazing around the island<\/p><\/div>\n

The majority of our fieldwork on Derawan focuses on unraveling the interactions between seagrasses, turtle grazing and increasing nutrient loads. A fancy fieldwork station is lacking but this stimulates to interact a lot with the (families of the) local fisherman that have a lot of knowledge about the ecosystems.<\/p>\n

\"\"<\/a>

On a small island with 1500 people we always have enough attention from the local kids (left). Daily fieldwork life, working on exclosures 400 meters offshore of the island (right)<\/p><\/div>\n

Working on such a remote island is amazing because you are surrounded by marine life such as green turtles, mantas, dolphins, frog fish, and (my favorite) the robust ghost pipefish (looks like a Thalassia<\/em> leaf). But on the other hand you also have to plan your experiment well and buy your materials a full day travelling away, or even further. And don\u2019t step in a stingray like I did because this will definitely slow down your fieldwork.<\/p>\n

\"\"<\/a>

180 degrees panorama from the Telkom tower<\/p><\/div>\n","protected":false},"excerpt":{"rendered":"

Every fortnight we feature a seagrass meadow from around the world. This week, Marjolijn Christianen shares her experiences working in the beautiful tropical island of Derawan in Indonesia. Marjolijn is currently a PhD student at Radboud University in The Netherlands. She has a blog detailing her experiences working with turtles and seagrass. ——————————- by Marjolijn […]<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"jetpack_post_was_ever_published":false,"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":false,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"font":"","enabled":false},"version":2}},"categories":[7],"tags":[5,9],"class_list":["post-102","post","type-post","status-publish","format-standard","hentry","category-nftf","tag-notes-from-the-field","tag-se-asia"],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"","jetpack_shortlink":"https:\/\/wp.me\/p2Cwsq-1E","jetpack-related-posts":[{"id":146,"url":"https:\/\/wsa.seagrassonline.org\/blog\/archives\/146","url_meta":{"origin":102,"position":0},"title":"Notes from the Field: Barang Lompo, South Sulawesi","author":"Siti","date":"1 February, 2012","format":false,"excerpt":"Every fortnight we feature a seagrass meadow from around the world. This week, I thought I'd take a stab at writing about a recent trip I made to a seagrass meadow on a sand cay called Barang Lompo in South Sulawesi. By Siti M. Yaakub (text) & Marjolijn Christianen (photos)\u2026","rel":"","context":"In "Notes from the field"","block_context":{"text":"Notes from the field","link":"https:\/\/wsa.seagrassonline.org\/blog\/archives\/category\/nftf"},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/wsa.seagrassonline.org\/blog\/wp-content\/uploads\/2012\/02\/Combined-map.jpg?resize=350%2C200","width":350,"height":200},"classes":[]},{"id":304,"url":"https:\/\/wsa.seagrassonline.org\/blog\/archives\/304","url_meta":{"origin":102,"position":1},"title":"Notes from the field: Samos, Greece","author":"Siti","date":"2 January, 2014","format":false,"excerpt":"Every so often we feature a seagrass meadow from around the world. This week, Richard \u201cRJ\u201d Lilley reports from Samos, a Greek Island in the North Aegean. He is a PhD student at the interdisciplinary Sustainable Places Research Institute at Cardiff University and is exploring seagrass links to food security.\u2026","rel":"","context":"In "Notes from the field"","block_context":{"text":"Notes from the field","link":"https:\/\/wsa.seagrassonline.org\/blog\/archives\/category\/nftf"},"img":{"alt_text":"RJ_Greece1","src":"https:\/\/i0.wp.com\/wsa.seagrassonline.org\/blog\/wp-content\/uploads\/2014\/01\/RJ_Greece1-300x200.jpg?resize=350%2C200","width":350,"height":200},"classes":[]},{"id":180,"url":"https:\/\/wsa.seagrassonline.org\/blog\/archives\/180","url_meta":{"origin":102,"position":2},"title":"Notes from the field: Reflections from down under","author":"Siti","date":"4 May, 2012","format":false,"excerpt":"22nd May is International Day for Biodiversity and the theme for 2012 is Marine Biodiversity. In celebration, we will be featuring a series of articles on seagrass. This week, Michael Durako writes about his experiences visiting North Queensland, Australia. ---------------------------------------------------------- Photos and text by Michael J. Durako\u00a0\u00a0 During the Fall\u2026","rel":"","context":"In "Notes from the field"","block_context":{"text":"Notes from the field","link":"https:\/\/wsa.seagrassonline.org\/blog\/archives\/category\/nftf"},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/wsa.seagrassonline.org\/blog\/wp-content\/uploads\/2012\/05\/MD1.jpg?resize=350%2C200","width":350,"height":200},"classes":[]},{"id":199,"url":"https:\/\/wsa.seagrassonline.org\/blog\/archives\/199","url_meta":{"origin":102,"position":3},"title":"Notes from the Field: South Florida","author":"Siti","date":"23 May, 2012","format":false,"excerpt":"22nd May is International Day for Biodiversity and the theme for 2012 is Marine Biodiversity. In celebration, we will be featuring a series of articles on seagrass. This week, Elizabeth \u201cZ\u201d Lacey writes about her experiences in the long-term monitoring project in the seagrass beds of South Florida under the\u2026","rel":"","context":"In "Notes from the field"","block_context":{"text":"Notes from the field","link":"https:\/\/wsa.seagrassonline.org\/blog\/archives\/category\/nftf"},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/wsa.seagrassonline.org\/blog\/wp-content\/uploads\/2012\/05\/FLO1-300x214.jpg?resize=350%2C200","width":350,"height":200},"classes":[]},{"id":281,"url":"https:\/\/wsa.seagrassonline.org\/blog\/archives\/281","url_meta":{"origin":102,"position":4},"title":"Notes from the Field: Turks & Caicos Islands","author":"Siti","date":"1 June, 2013","format":false,"excerpt":"Every so often (but only as often as we receive contributions) we feature a seagrass meadow from around the world. This week, Richard (RJ) Lilley reports from South Caicos is the Turks and Caicos Islands. 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Z is finishing her Ph.D. at Florida International University in Miami, Florida. --------------------------------------- Photos and text by Z Lacey I\u2026","rel":"","context":"In "Notes from the field"","block_context":{"text":"Notes from the field","link":"https:\/\/wsa.seagrassonline.org\/blog\/archives\/category\/nftf"},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/wsa.seagrassonline.org\/blog\/wp-content\/uploads\/2012\/02\/Fig-1.jpg?resize=350%2C200","width":350,"height":200},"classes":[]}],"jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/wsa.seagrassonline.org\/blog\/wp-json\/wp\/v2\/posts\/102","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/wsa.seagrassonline.org\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/wsa.seagrassonline.org\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/wsa.seagrassonline.org\/blog\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/wsa.seagrassonline.org\/blog\/wp-json\/wp\/v2\/comments?post=102"}],"version-history":[{"count":0,"href":"https:\/\/wsa.seagrassonline.org\/blog\/wp-json\/wp\/v2\/posts\/102\/revisions"}],"wp:attachment":[{"href":"https:\/\/wsa.seagrassonline.org\/blog\/wp-json\/wp\/v2\/media?parent=102"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/wsa.seagrassonline.org\/blog\/wp-json\/wp\/v2\/categories?post=102"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/wsa.seagrassonline.org\/blog\/wp-json\/wp\/v2\/tags?post=102"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}