Recent Submissions

  • Diversity of Coral Reef Fishes in Larak Island, Persian Gulf

    Khatami, S.; Valinassab, T.; Tavakoli-Kolour, P.; Yahyavi, M.; Behzadi, S. (2012)
    The coral reefs are one of the most important and rich ecosystems in the world and are considered as major habitat for different species group of fishes. Fourteen islands are found in the northern Persian Gulf including Larak Island of which the coral regions around this island were determined and then for sampling, 6 stations were randomly selected by Manta Tow method in July to December 2010. The identification was conducted using Visual Census technique in 6 stations. A total of 54 species belong to 41 genera and 23 families were identified and amongst them the abundant species group belonged to Pomacentridae family with 11 species. The results indicated that however the stations were far from urban area; the species diversity has been higher.
  • Mass coral bleaching in the northern Persian Gulf, 2012

    Kavousi, J.; Tavakoli-Kolour, P.; Mohammadizadeh, M.; Bahrami, A.; Barkhordari, A. (2014-09)
    Coral bleaching events due to elevated temperatures are increasing in both frequency and magnitude worldwide. Mass bleaching was recorded at five sites in the northern Persian Gulf during August and September 2012. Based on available seawater temperature data from field, satellite and previous studies, we suggest that the coral bleaching threshold temperature in the northern Persian Gulf is between 33.5 and 34°C, which is about 1.5 to 2.5°C lower than that in the southern part. To assess the bleaching effects, coral genera counted during 60-minute dives were categorized into four groups including healthy, slightly bleached (<50% bleached tissue), mostly bleached (>50% bleached tissue) and fully bleached colonies. The anomalously high sea surface temperature resulted in massive coral bleaching (~84% coral colonies affected). Acropora spp. colonies, which are known as the most vulnerable corals to thermal stress, were less affected by the bleaching than massive corals, such as Porites, which are among the most thermo-tolerant corals. Turbid waters, suggested as coral refugia against global warming, did not protect corals in this study since most affected corals were found in the most turbid waters. The 2012 bleaching in the northern Persian Gulf was relatively strong from the viewpoint of coral bleaching severity. Long-term monitoring is needed to understand the actual consequences of the bleaching event on the coral reefs and communities.
  • Outbreak of growth anomalies in coral communities of Qeshm Island, Persian Gulf

    Tavakoli-Kolour, P.; Kavousi, J.; Rezai, H. (2015)
    Reports on the outbreaks of coral diseases are on the rise, stating that diseases are considered to be one of the main drives in the decline of global coral reefs. In this study, the outbreak of growth anomalies (GAs) in coral communities of the south of Qeshm Island in the Persian Gulf is reported. Despite a previous report on the localized GAs on a few colonies, this is the first report of GA outbreak from the Persian Gulf, in which 28 ± 11 % (±SE) and 21 ± 13 % of P. daedalea and Porites colonies contracted GAs in July 2012. A year later, we recorded GAs on 37 ± 07 % of P. daedalea and 23 ± 12 % of Porites colonies. Pearson’s correlation test showed a strong positive relationship between coral colony size and the number of GAs (r = 0.907, p\0.05). Further investigation is needed to understand the cause of GAs, their progress trend, and prospective impacts on the coral communities at our studied site.
  • Competitional settlement of brown alga Iyengaria stellata and soft coral Zoanthous sansibaricus on muddy and muddy-rubble intertidal substrate in the Hormuz island

    Bahmani, Ghazaleh; Alavi-Yeganeh, Mohammad Sadegh; Seyfabadi, Seyed Jafar; Tavakoli-Kolour, Parviz (2017)
    The effect of substrates on the surface cover by the soft coral, Zoanthus sansibaricus, and the brown alga, Iyengaria stellata, and their competitional condition, was compared in Hormuz Island by estimating of coverage area in 40 quadrates (50×50 cm). This soft coarl (Zoanthid) is a dominant species in the island’s intertidal zone and I. stellata is a dominant macroalgea most of the year. Significant negative correlation (p<0.01; r =-0.607) revealed competition between the two species for settlement on the two substrates. Soft coral with 61.7% coverage was dominant vs. 16.8% for brown algae on muddy-rubble substrate, but on sandy-rubble substrate, the brown algae was dominant with 37.8% coverage vs. 19.5% for the soft coral. It seems that better competitional conditions in settlement on unconsolidated substrate have some advantages for Z. sansibaricus.
  • Coral reefs and community around Larak island (Persian Gulf)

    Mohammadizadeh, Maria; Tavakoli-Kolour, Parviz; Rezai, Hamid (2013)
    Field surveys pertaining to coral reef studies were performed from November 2010 to August 2011 around Larak Island in the Persian Gulf. The Line Intercept Transect (LIT) method was applied to record biotic and abiotic components of the coral reefs at two sites around Larak Island: North East (NE) and South West (SW) with two stations per site. Mean "Live Coral Coverage" (LCC) and “Dead Coral Coverage” (DCC) at SW 21.74% ± 1.92%, 4.58% ± 0.65%and NE sites were 5.69% ± 0.54%, 35.64% ± 3.28% respectively. Dead Coral Coverage was more prevalent in the NE than in SW. Based on Mann-Whitney U-test LCC and DCC showed significant difference (p< 0.05) among these two sites, (p< 0.05); The Kruskal-Wallis test also showed significant difference (p< 0.05) among four stations within two sites. This study indicated that coral communities of the NE site have been more destroyed by human impacts such as municipal run-off, breakwater construction, trap fishing, over-fishing and several other human activities.
  • Identification and assess anthropogenic impacts on species richness of coral reef fishes in Larak Island, Persian Gulf

    Khatami, S.; Valinassab, T.; Tavakoli-Kolour, Parviz (2014)
    Coral reefs are amongst the most important and rich ecosystems in the world and are provide habitat for a diverse range of species groups of fishes and invertebrates. Larak Island is one of fourteen islands found in the Persian Gulf which was selected for this study. The reef fish distribution around this island was identified and then for sampling, six stations were randomly selected by Manta Tow method. The identification was conducted using visual census technique in all stations. A total of 54 species belonging to 42 genera and 23 families were identified and amongst them the abundant species group belonged to family Pomacentridae with 11 species. The results indicated that further the stations were from an urban area higher species richness was.
  • A Study on Diet Composition and Feeding Habitats of Sillago sihama (Forsskål, 1775) in Coastal Waters of Bandar Abbas

    Mohammaizadeh, Flora; Tavakoli-Kolour, Parviz; Khajkeramaldini, Marzieh; Mohammadizadeh, Maria; Bahri, Amir Houshang (2013)
    The diet composition and feeding habits of Sillago sihama , were studied in the northern Persian Gulf restricted to coastal waters of Bandar Abbas within 14 months period, from July 2007 up to August 2008. Biometrical and anatomical measurements were carried out, and biological surveys were conducted on 572 specimens (238 Male and 306 Female). These samples were collected from coastal waters of Bandar Abbas by pool and line and Moshta. The measurements of the minimum and maximum total lengths and weights were 10.6 to 45.5 cm and 8.58 to 196.27 g, respectively. The calculated level of (R2) (correlations of total length & weight), indicated correlations between length and weight of this fish, and b was 2.75 that shows the growth is isometric. The results indicated that this species, having the Relative Length of Gut, RLG = 0.47± 0.15, is carnivorous. Examining the changes in the index of stomach emptiness by the percentage of CV = 59.88% indicates that this fish is Moderate feeder. Proven by the fact that benthos was taken as principle food, Crustacean, Shrimps, and fish as secondary food and other kinds of food as random. Among the food items, benthos, crustaceans, razor clam, crab, shrimp, fish, polychaetes, oligocheata, clams, shells, detritus, hermit crab, crayfish, were 59.15, 12.82, 6.22, 5.99, 5.91, 3.09, 2.55, 2.05, 0.83, 0.56, 0.46, 0.20 and 0.16 respectively. The level of feeding increased in February, before spawning and decreased in May, simultaneously with the spawning season.
  • Mass Mortality of Porites Corals on Northern Persian Gulf Reefs due to Sediment-Microbial Interactions

    Kavousi, Javid; Tavakoli-Kolour, Parviz; Barkhordari, Abbas; Bahrami, Arezoo (2013)
    Little information is available on coral diseases in the Persian Gulf; however, in the recent years, reports of coral diseases increased in particular from Iranian side of the Persian Gulf. In this paper we report a White Mat Disease resulting in mass mortality of Porites colonies at Hormuz Island. This outbreak infected 96% of all Porites colonies and killed 58±30% (mean ± SD) of all Porites tissues.
  • A density study of order Zoantharia in northern and southern coasts of Hormuz Island

    Bahmani, G.; Seifabadi, J.; Alavi-Yeganeh, M. S.; Tavakoli-Kolour, P. (2015)