Seagrass Habitat of Mourilyan Harbour: annual monitoring report: 2015

Other Publication ResearchOnline@JCU
Reason, Carissa;York, Paul;Scott, Emma;McKenna, Skye;Rasheed, Michael
Abstract

[Key Findings] 1. Overall seagrasses in Mourilyan Harbour remained in a very poor state with the continued absence of seagrass in all the intertidal monitoring meadows. 2. The subtidal channel meadow reduced in size and mean biomass from the previous year but remained in a good condition by historical standards. 3. Only one species (Halophila decipiens) was present in the monitoring meadows, however the first study of the broader harbour environment since 2000 recorded small meadows and isolated patches of Halodule uninervis, Enhalus acoroides and Halophila ovalis elsewhere in the harbour. 4. The foundation species (Zostera muelleri and Ha lodule uninervis) that had been continually present since monitoring began in 1993 until 2009 were absent for the sixth consecutive year. 5. The lack of recovery in foundation species despite improved growing conditions from 2012 may be due to a lack of seagrass propagules. Seedbank surveys over the last four years have found very low densities of Z. muelleri seeds, and in 2015 seeds were entirely absent. 6. In a regional context, seagrass at all long-term monitoring sites in the wet and dry tropics regions und erwent severe declines from 2009-11. Meadows to the north (Cairns Harbour) and south (Townsville) have now shown substantial recovery. Mourilyan Harbour remains the only location where no recovery of the key high biomass foundation species has occurred. 7. It is likely that assisted restoration will be required to re-establish viable Zostera muelleri in Mourilyan Harbour, given the lack of a seedbank and the areas isolation from any healthy nearby populations from which seeds or propagules could disperse.

Journal

N/A

Publication Name

N/A

Volume

16/20

ISBN/ISSN

N/A

Edition

N/A

Issue

N/A

Pages Count

46

Location

N/A

Publisher

TropWATER, James Cook University

Publisher Url

N/A

Publisher Location

Cairns, QLD, Australia

Publish Date

N/A

Url

N/A

Date

N/A

EISSN

N/A

DOI

N/A