Rottnest Island Seagrass Monitoring Program
(December 2017 - February 2018)
WADDI has completed the 2017/2018 Rottnest Island seagrass monitoring season!
A big thank you to WADDI members Kathy Murray, Georgia Hall, Denisse Fierro Arcos, Alicia Sutton and Paul Day, who participated in the third weekend of seagrass monitoring (3-5thFeb)! The weather was the best it has ever been across the three days, which meant we had no set backs weather wise this season and could complete 10 bays in three weekends!
We left for Rottnest early Saturday afternoon and, after a quick detour past the research station, we made our way to the southern end of Thomson Bay to try and bust out monitoring of a full bay. With three trained divers in the water, we were able to complete the site in just under 2 hours, measure several species of seagrass, and work up a big appetite for dinner!
Green Island was on the cards first thing on Sunday morning. With 18 m of viz and hardly any wind and swell, two new WADDI members were successfully trained in seagrass monitoring methods. If only all of our new members could have such perfect wind and water conditions!
After having a rest in the sun with the beautiful view of Green Island, and shovelling a couple of sandwiches down the hatch, we all loaded back into the buggies and set off to Stark Bay. Now with four trained divers in the water, we were done in no time, and successfully got Kathy and Denisse packed and ready for the afternoon ferry back to Fremantle- just in the nick of time!
Settling in back at the research station with a traditional meal of pasta, Paul, Alicia and Georgia got stuck into measuring collected specimens of Amphibolis, where we’re always hoping to be the lucky one to pick a stem with the least amount of counting to do!
On this weekend, we decided to stay on for Monday morning to finish of a site in the middle of Thomson Bay, which can be very busy with boats on the weekend! Armed with the Pink Flamingo, we were ready to be as visible as we could be in a busy bay so that we could complete our mission! The Pink Flamingo is now a fully fledged WADDI member and will be joining us every season.
Volunteer trip story by David Juszkiewicz
It was a beautiful Friday afternoon as we all assembled at the B Shed, Fremantle. There on the dock lay a large aluminum crate labeled WADDI, a beacon for the team to meet. Once all the members arrived and introduced themselves the game of Tetris began to fit all of the tanks and diving equipment into the crate. After considerable manoeuvring and shuffling of the equipment, we boarded the ferry. Quite quickly we got to know each other and all shared a common interest in Marine science and diving. The first thing on the agenda for discussion was the weather and how many sites optimism would allow us to carry out. We all looked at the Sunday weather, and the forecast 35 knot winds and 3 m swell that was going to smash the coast of Rottnest. With such beautiful weather during the week who would’ve expected a cold front would greet us in summer.
As we arrived at Rottnest, Alicia greeted us at the main jetty with two buggies which would be our transport for the weekend. We loaded them up with our gear and off we drove into the sunset towards our accommodation called the Stables. We were happy to share the accommodation with UWA students completing their honors on the western rock lobster. After unpacking, we headed off to the pub for a counter meal and to discuss our plans for Saturday. At the pub, we were informed of a comedy night which required silence from the patrons and the possibility of foiling our plans to discuss the schedule for the coming days. As the delicious meals were served and discussion broke out on seagrass monitoring activities, we were shushed continuously by an employee. The shushing was somewhat louder than our quite chatter which became more amusing and hilarious than the comedy going on in the background. After making a rough plan and decision on a start time, we walked back to camp, and everyone was sound asleep very fast.
At the crack of dawn…. Well, 8:30… We managed to get our things together and head over to our first site. Rocky Bay East. It was quite a hike with all the equipment down to the beach though worthwhile and it was important to have the correct equipment in the event of an emergency. Alicia and Paul briefed us, and JH and I listened to instructions. A little overwhelmed about the importance and accuracy of shoot counts. Both having a marine degree, we did value the importance. After getting kitted out with a tape, quadrat and slate we set out to the site. After the location being determined and transects laid it was time for JH and myself to get some training from Paul. We all submerged and watched wide-eyed as Paul gently laid the quadrat. One by one he followed the shoots into the sediment and systematically moved along shoot by shoot. JH and myself watched patiently awaiting our turn. It wasn’t until the end we had wished we had counted the shoots along with him to have a rough estimate for our counts. After Paul was done, it was our turn, and with nervousness but precision we counted, and on completion, we compared our numbers to Pauls. We were only a couple off, what an achievement and smiles gleamed on both our faces with Alicia yelling from the shore well done. We had one more go at calibrating and were accurate within one shoot, success. JH and myself where stoked, now we could be beneficial to the project and start counting shoots on our own. The team quickly became efficient and functioned as a scientific unit to produce quality data whilst surrounded by what seemed like thousands of marine molluscs engulfing the Posidonia seagrass.
Our first site was done by 15:00 on Saturday and we decided to skip lunch in the town after filling ourselves on burger-ring peanut butter sandwiches on the beach. We packed up and scurried up to our final site of the day Geordie Bay. Alicia joined us in the water and Kevin was our eyes from the land ensuring our safety and rushing any equipment we needed to the shore. As we swam to the green mooring which was close to our Posidonia site, we went past a large stingray with at least a 1.5 m wingspan. As we commenced our counts, there was a point where darkness fell over the quadrat, as it happened again, I looked up and my heart stopped, it was the large stingray passing overhead swimming past curiously and maybe somewhat longing to help in our effort for the conservation of its Posidonia habitat. With adequate training from Rocky Bay, it did not take long for the team to complete the Geordie Bay site and we were out of the water by 5:40 with an urgent rush to collect our filled tanks and drop off the empties for filling to be ready on the next day. As we drove back to camp the weather starting turning and the clouds were rolling in, a sign of what to expect on Sunday and a worry was coming over the team on whether the weather would prevent us from completing a site the next day.
The next morning we arose and decided to make a reconnaissance trip to scope out the potential of doing our final site of the trip at Thompson Bay. Kevin tapped me on the shoulder and pointed out the Rottnest wind turbine spinning more furiously then normal which may prove to be an indicator of what to expect at Thompson Bay. As we approached the site it was quiet through the settlement and there was a blue horizon and calm water awaiting the team for another sampling day. Thompson Bay was entirely sheltered from the cold front that was approaching Rottnest from the SW so we headed back to camp, collected the rest of the team and attacked our final site. With precision and efficiency we completed the site though we could feel the gradual change in swell during the dive with changing conditions quite noticeable as the monitoring reached the end. As we packed our equipment, the team discovered that the late afternoon ferries had been delayed as a result of the change of weather. With prompt action from the team leader, we changed our ferry times and rushed back to camp to clean and pack up. With a great team effort, we were able to clean and pack everything, give back our transport, and be on the ferry with ten minutes to spare. The swell was picking up, and it was a race against the storm to get back to Fremantle B shed. On arrival in Fremantle, we offloaded, packed our gear into the cars and as we said our goodbyes to the fantastic team the rain started to pour and the wind began to howl. With that our timing was impeccable. Three sites completed, returned home early, and a well worthwhile WADDI monitoring trip.