Parrotfish Sparisoma Cretense Research Articles

Trends in abundance indices derived from commercial fisheries for priority marine stocks in the Azores.

Large-scale assessments of fish and shellfish populations may be valuable for identifying the impacts of fishing pressure on stocks, but they are rarely possible due to a lack of long-term datasets. In this study, a two-part mixed-effect model for lognormal data was used to obtain historical abundance indices for 16 priority fish and shellfish stocks in the Azores region derived from catch per unit effort (kg per day at sea per vessel) and landing per unit effort (kg per landing per vessel). This data was obtained over the past 30 years under the EC Data Collection Framework and, in addition to information on effort and catch, included details about the fishing operation such as quarter, vessel length and fishing gear. This information was analysed to investigate how abundance indices changed over the years, verify if trends from different data sources were different and, if possible, relate these results to the population and fishery dynamics. The abundance indices derived from both datasets were generally in agreement with each other. Declining trends have been observed for some commercially important species, such as forkbeard Phycis phycis, European conger Conger conger, parrotfish Sparisoma cretense, red scorpionfish Scorpaena scrofa, offshore rockfish Pontinus kuhlii, common spiny lobster Palinurus elephas, splendid alfonsino Beryx splendens and alfonsino B. decadactylus, which is concerning because they are particularly slow-growing, long-lived and have low natural mortality, making them susceptible to overfishing. The results of this study are very important and should help future stock assessment and management initiatives.

The Gyaros island marine reserve: A biodiversity hotspot in the eastern Mediterranean Sea.

Since July 2019, Gyaros island in the central Aegean Sea, enjoys the status of a partial Marine Protected Area (MPA), allowing for exploitation by small-scale fishers following specific spatio-temporal restrictions. The need for assessing the effectiveness of the MPA in the future, led MAVA Foundation to fund a knowledge survey project aiming to serve as a baseline for future reference. A series of experimental fishing surveys took place with static nets, the outcomes of which are presented herein. From June 2018 to September 2020, a series of 8 fishing excursions with a total of 40 experimental fishing sets with bottom static nets were realized in 5 set locations around Gyaros island, inside the MPA protection zone. A total of 75 species were identified; the most abundant species, in terms of biomass, being: parrotfish-Sparisoma cretense, red scorpionfish-Scorpaena scrofa, common spiny lobster-Palinurus elephas, red porgy-Pagrus pagrus, little tunny–-Euthynnus alletteratus, Mediterranean moray-Muraena helena, lesser spotted dogfish -Scyliorhinus canicula, forkbeard-Phycis phycis, surmullet-Mullus surmuletus, common cuttlefish-Sepia officinalis and common Pandora-Pagellus erythrinus. A comparison with similar data in adjacent areas outside the MPA allowed for assessing the effectiveness of the MPA based on four indicators: species diversity index, species relative biomass index, key predator species abundance, and alien fish abundance. Based solely on the experimental fishing trials, the MPA seems to be functioning, since both species diversity and abundance were higher within the protected area. However, its performance may still not be considered as optimal, as this is indicated by the large proportion of undersized key predators (e.g. groupers), although more abundant and larger than the ones residing outside the MPA.

Northward Spread of the Parrotfish Sparisoma cretense (Teleostei: Scaridae) in the Mediterranean Sea: An Update on Current Distribution with Two New Records from Sardinia

The parrotfish Sparisoma cretense, a marine species native to the eastern and southern coastal areas of the Mediterranean, has extended its distribution northward. Here, we provide an update on its distribution based on currently published data and two new records from the coastline of Sardinia, Italy (central-western Mediterranean). The survey methods were scuba diving and spearfishing: one specimen of S. cretense was caught along the Argentiera coastline (northwest Mediterranean) and the others were photographed in the Gulf of Orosei, Osalla Bay (central-eastern Mediterranean). A literature update, together with new records, documents the distribution of this species in the northernmost areas of the Mediterranean. Probably a result of global warming, the ongoing northward expansion of S. cretense highlights the need for sampling campaigns to obtain timely updates on population and distribution of this thermophilic species.

Dikili Körfezi’nde (Kuzey Ege Denizi, Türkiye) Termofil Akdeniz Papağan Balığı Sparisoma cretense (Linneaus, 1758) (Teleostei: Scaridae)’nin Bulunuşu

On November 2019, one mature male specimen of the Mediterranean parrotfish Sparisoma cretense (L.) was caught by a long line in Dikili Bay. In addition to the relevant literature, this paper declares the northernmost distribution of S. cretense in the northern Aegean Sea, Turkey. This report is the first observation for the location. Here, detailed morphometric and meristic characteristics of this species are given.

Importance of recreational shore angling in the archipelago of Madeira, Portugal (northeast Atlantic)

In 2017, a total of 4825 licences were issued for shore angling in Madeira. Surveys were conducted on 734 anglers, some in the government fisheries office during the licence request and others during the fishing activity. Shore angling is practised throughout the year, mostly at weekends and during day time, and with an increase in summer. More than 60% of the anglers are unemployed, have low incomes, and spend on average €254 per person per year on this activity, adding up to a total of €1.16 million per year. Shore angling average number of fishing days per year per fisher was 65.1±62.0 and the average catch per unit of effort was 0.35±0.26 kg/angler/hour. The estimated total annual catch was 520.7 t. Forty-three teleost species, 2 elasmobranchs and 6 invertebrates were identified in the catches. Despite the limitations and inaccuracies inherent to the surveys, they still provided valuable information and gave a general perception of the recreational shore fisheries in Madeira. The possible impact on the most captured species, such as the white seabream, Diplodus sargus (Linnaeus, 1758), and the parrotfish Sparisoma cretense (Linnaeus, 1758), should be analysed because high fishing pressure could affect populations and ecosystems.

Plankton community of trafficked ports as a baseline reference for Non Indigenous Species arrivals. Case study of the Port of Bar (South Adriatic Sea)

Plankton (ichthyo, zoo and phyto) communities were studied in the temperate shallow waters of the Port of Bar, one of the main cargo ports on the south-eastern Adriatic coast. Sampling was undertaken in February, April, June and October 2015 at 12 stations using the BALMAS Port Baseline Survey protocol. The research was conducted to determine the presence of invasive and potentially toxic plankton species in the port.The most dominant species of ichthyoplankton were eggs and larvae of families Engraulidae, Bothidae and Sparidae with a dominance of Engraulis encrasicolus, Arnoglossus laterna and Diplodus annularis. In addition to ichthyoplankton, sampling of phyto and zooplankton was performed to estimate the abundance and diversity of species.The most numerous zooplankton species throughout investigated period were Penilia avirostris, Euterpina acutifrons, Oithona nana, Acartia clausi, Centropages kroyeri, Paracalanus parvus, Oncaeidae and larvae of Bivalvia. One very unusual occurrence was the spawning of parrotfish Sparisoma cretense (Linnaeus, 1758), a species with Atlantic origin and tropical affinities, whose presence throughout the Mediterranean has shown an increasing trend over the last decade. The most dominant species of phytoplankton were the diatoms Chaetoceros affinis and Chaetoceros spp., Asterionellopsis glacialis, Pseudo-nitzschia spp., Thalassionema nitzschioides, and dinoflagellates Gymnodinium spp. and Prorocentrum triestinum. The potentially toxic species from genus Pseudo- nitzschia reached an abundance of 104 cells L-1. Toxic dinoflagellates Prorocentrum cordatum and P. micans reached values of 103 cells L-1.Although there were no HAOP species found during the survey, presence of several potentially toxic and toxic phytoplankton species whose impact is not sufficiently known indicates the necessity of introduction of regular monitoring activities and definition of preventive protection measures.

Seawater warming at the northern reach for southern species: Gulf of Genoa, NW Mediterranean

Global warming is facilitating the poleward range expansion of plant and animal species. In the Mediterranean Sea, the concurrent temperature increase and abundance of (sub)tropical non-indigenous species (NIS) is leading to the so-called ‘tropicalization’ of the Mediterranean Sea, which is dramatically evident in the south-eastern sectors of the basin. At the same time, the colder north-western sectors of the basin have been said to undergo a process of ‘meridionalization’, that is the establishment of warm-water native species (WWN) previously restricted to the southern sectors. The Gulf of Genoa (Ligurian Sea) is the north-western reach for southern species of whatever origin in the Mediterranean. Recent (up to 2015) observations of NIS and WWN by diving have been collated to update previous similar inventories. In addition, the relative occurrences of both groups of southern species have been monitored by snorkelling between 2009 and 2015 in shallow rocky reefs at Genoa, and compared with the trend in air and sea surface temperatures. A total of 20 southern species (11 NIS and 9 WWN) was found. Two WWN (the zebra seabream Diplodus cervinus and the parrotfish Sparisoma cretense) and three NIS (the SW Atlantic sponge Paraleucilla magna, the Red Sea polychaete Branchiomma luctuosum, and the amphi-American and amphi-Atlantic crab Percnon gibbesi) are new records for the Ligurian Sea, whereas juveniles of the Indo-Pacific bluespotted cornetfish Fistularia commersonii have been found for the first time. While temperature has kept on increasing for the whole period, with 2014 and 2015 being the warmest years since at least 1950, the number of WWN increased linearly, that of NIS increased exponentially, contradicting the idea of meridionalization and supporting that of tropicalization even in the northern sectors of the Mediterranean basin.

Differences in herbivory intensity between the seagrass Cymodocea nodosa and the green alga Caulerpa prolifera inhabiting the same habitat

Seagrasses are frequently found mixed with other macrophytes, e.g., green macroalgae. We aimed to assess whether the magnitude of herbivory differed between two coexisting macrophytes, the seagrass Cymodocea nodosa (Ucria) Ascherson and the green seaweed Caulerpa prolifera (Forsskål) Lamouroux, at Gran Canaria Island (eastern Atlantic). Both in situ (field) and aquaria experimentation demonstrated a larger intensity of herbivory (between ca. 4–8 times) on C. prolifera than C. nodosa. At the scale of meadows, herbivorous fish abundance predicted the intensity of herbivory, in particular by the parrotfish Sparisoma cretense. A plant physical attribute (“force-to-fracture”) negatively correlated with a larger consumption on C. prolifera, while differences in total phenolic compounds between both macrophytes were insignificant. Importantly, herbivory marks (bites) were significantly larger (ca. two times) on C. nodosa leaves than in C. prolifera fronds, so differences in the magnitude of herbivory between C. nodosa and C. prolifera were dependent on herbivorous size.

Morphological characterisation and phylogenetic relationships of Zschokkella candia n. sp. from the gall-bladder of Sparisoma cretense (L.) (Perciformes: Scaridae) in the Sea of Crete off Greece

A new myxosporean parasite, Zschokkella candia n. sp., from the gall-bladder of the wild parrotfish Sparisoma cretense (L.) (Perciformes: Scaridae) is described based on light and scanning electron microscopy. Mature spores are elliptical, with mean dimensions 11.2 ± 0.5 × 7.8 ± 0.1 μm and possess spherical polar capsules with mean diameter of 2.3 ± 0.3 μm. The new species is differentiated from other similar species of the genus based on spore morphology, its coelozoic life-style and molecular data. The phylogenetic tree constructed using maximum likelihood analysis of small subunit (SSU) rDNA sequence data complements the characterisation of Zschokkella candia n. sp. by defining its phylogenetic position among the species of Zschokkella Auerbach, 1909 sequenced to date. The phylogenetic analysis supports the existing knowledge on the complicated polyphyletic relationships among the members of the genus Zschokkella.

Unusual captures of teleost species from the northern Coast of Tunisia (central Mediterranean)

A survey conducted off the northern Tunisian coast allow to collect specimens belonging to species rarely captured in the area, such as longjaw snake eel Ophisurus serpens (Linnaeus, 1758), bluntsnout snake eel Echelus myrus (Linnaeus, 1758), Mediterranean parrot fish Sparisoma cretense (Linnaeus, 1758) and sharksucker Echeneis naucrates (Linnaeus, 1758). All specimens are shortly described in the present paper, including morphometric measurements and meristic counts. Their distribution in the area and the Mediterranean Sea is commented and discussed.

Abundance and biomass of the parrotfish Sparisoma cretense in seagrass meadows: temporal and spatial differences between seagrass interiors and seagrass adjacent to reefs

Seagrass habitats are relevant for numerous nearshore fish species, particularly as nursery grounds. Seagrass meadows are often interspersed with other habitats, what can alter the distribution and abundance of seagrass ichthyofauna. This research aimed to determine whether there is a change in the abundance and biomass of the parrotfish, Sparisoma cretense, in seagrass meadows (Cymodocea nodosa) with varying proximity from rocky reefs, specifically seagrass interiors (>200 m away from reefs) vs. seagrass adjacent to reefs (<10 m away). Sampling was undertaken using a seine net and underwater visual census through an entire annual cycle. Adults were predominantly observed in seagrass adjacent to reefs, which seem to be restricted to incursions of large-sized parrotfish from adjacent reefs. Juvenile abundance did not significantly differ between seagrass interiors and seagrass adjacent to reefs; however, juvenile biomass was greater in seagrass meadows adjacent to reefs compared to those far away from reefs. This pattern was consistent through times for both sampling techniques. These results suggest a transition of juvenile parrotfish from seagrass interiors to seagrass near reefs, so juveniles are located in the vicinity of their adult habitat, i.e. rocky reefs.

Movement patterns of the parrotfish Sparisoma cretense in a Mediterranean marine protected area

Understanding the movements of exploited fish has become a major concern for several management and conservation initiatives, such as the implementation of well designed marine protected areas. Movements of an important recreational target species from the Mediterranean Sea, the parrotfish Sparisoma cretense, were determined in a marine protected area using passive acoustic telemetry, to evaluate site fidelity and homing, quantify home range and identify temporal patterns. Six adult parrotfish (20.8–29.8 cm total length) were caught along the north-eastern coast of Lampedusa (Italy) and surgically implanted with acoustic transmitters. Three fish were caught and released at the same site within the integral (i.e. “no entry-no take”) reserve, whereas the others were caught outside the reserve boundary and released at the mid reserve 0.5 km apart. Two of the three fish that were released away from the capture site demonstrated homing abilities. Four fish showed a strong site fidelity, whereas the others moved frequently in and out of the monitoring area. Home range sizes estimated over the period of monitoring (up to 207 days) varied from 70,387 to 256,398 m2, with core areas of 16,688 to 84,946 m2. Home range size did not differ significantly between day and night. Home ranges of all fish extended beyond the reserve boundaries, showing example of potential spillover into take zones. Temporal activity patterns of fish were diurnal with a dominant diel rhythm, likely due to a resting behaviour at night. Though not specifically designed to protect exploited fish, the marine reserve of Lampedusa seems adequate for the conservation and management of S. cretense.

Tropical fishes in a temperate sea: evolution of the wrasse Thalassoma pavo and the parrotfish Sparisoma cretense in the Mediterranean and the adjacent Macaronesian and Cape Verde Archipelagos

The northeastern Atlantic and the Mediterranean Sea share geological histories and display great faunal affinities. The majority of the Mediterranean species have Atlantic origins, with a few species with tropical affinities. These include the parrotfish Sparisoma cretense and the wrasse Thalassoma pavo that are restricted to the subtropical northeastern Atlantic, the Macaronesian archipelagos (Azores, Madeira, and Canaries) and the southern Mediterranean. The Pleistocene glaciations have been described as having different effects on the fauna of the two regions. During glacial peaks, Mediterranean waters remained warmer than those of the adjacent Atlantic. Within the eastern Atlantic, the effects of Pleistocene glaciations were differentiated. Here, we perform a comparative analysis focusing on T. pavo and S. cretense populations from the northeastern Atlantic and the Mediterranean to assess the effects of Pleistocene glaciations in these two species. Sequences from the mitochondrial control region were obtained and analyzed combining phylogeographic and demographic approaches. Gene flow between Atlantic and Mediterranean populations was shown to be very high. The Mediterranean populations of T. pavo and S. cretense showed high levels of genetic diversity, even in the eastern basin, pointing to an ancient colonization event. This suggests that both species must have been able to persist in the Mediterranean during the cold Pleistocene periods. Historical migration estimates revealed a Mediterranean towards Atlantic trend in the case of T. pavo, which may reflect the re-colonization of areas in the Atlantic by fish that survived the cold phases in relatively warmer Mediterranean refugia. Our data also showed that within the Macaronesian Archipelagos, migrations occurred from Madeira towards the Azores, for both T. pavo and S. cretense, thus supporting a post-glacial colonization of the Azores by fish that persisted in the warmer region of Madeira. Similar geographic distributions, thermal affinities, and means of dispersion for T. pavo and S. cretense resulted in a similar response to the effects of Pleistocene glaciations, as evidenced by identical phylogeographic patterns.

Spatial patterns in reproductive traits of the temperate parrotfish Sparisoma cretense

Reproductive biology and social behaviour of the parrotfish Sparisoma cretense was studied in the Azores Islands, northeast Atlantic, to characterize its spawning season and general reproductive biology in the region, to clarify the species mating system and associated spawning behaviours, and to evaluate the relationship between its reproductive traits and habitat features. S. cretense exhibits a dual mating system where males hold female harems within year-round territories or live in multi-male groups. Group behaviour predominates in smaller size classes, and territoriality in larger size classes. Males mature and become territorial earlier in life than females, and the best territories are held by larger males. The two behavioural modes are usually spatially segregated, with larger territorial fish preferring exposed and deeper reef ledges, and group fish occupying shallower, protected habitats. However, they frequently interact and overlap in space, especially during reproduction in the summer. Our findings indicate a highly competitive system and suggest that high quality spawning sites are important for the reproductive success of both types of fish. Patchiness of habitat along shorelines determines the relative distribution and equilibrium of territorial versus group fish. The complexity of this relationship between social structure and habitat might impact the populations’ productivity, and could influence the success of marine protected areas for this species.

Digestive enzymes along the alimentary tract of the parrotfish Sparisoma cretense

The digestive enzyme profile (total protease, total carbohydrase, alpha‐amylase and alpha‐glucosidase activity and capacity) along the digestive tract was investigated in vitro at different temperature levels (5, 18, 25 and 37° C) for the only Mediterranean species of parrotfish Sparisoma cretense. Sparisoma cretense (collected from the wild from south‐eastern Greece) exhibited very high potential for carbohydrate digestion, as well as relatively increased potential for protein digestion. Total protease activity and capacity was increased especially at neutral and alkaline pH levels and was similar in the anterior and posterior intestine. Total carbohydrase, alpha‐amylase and alpha‐glucosidase values were quite elevated at 37° C but relatively low at 5, 18 and 25° C. Total carbohydrase and alpha‐amylase capacity in the posterior intestine became increasingly important with elevated temperature, while the opposite was apparent for α‐glucosidase. These results suggest that, apart from the expected high potential for carbohydrate digestion exhibited, S. cretense also has the elevated capacity for protein digestion, although it lacks a specialized stomach and pyloric caeca.

Distribution of α amylase along the alimentary tract of two Mediterranean fish species, the parrotfish Sparisoma cretense L. and the stargazer, Uranoscopus scaber L

There is very little information available for the only Mediterranean species of parrotfish ( Sparisoma cretense) and its feeding habits, especially since most other parrotfish species are associated with coral reefs. The same lack of information is true for another fish species, the stargazer ( Uranoscopus scaber), which is carnivorous, and important for local fisheries in the Mediterranean. Comparative information is presented concerning the digestive activity and capacity for alpha amylase for these species with completely different feeding strategies, as well as main location(s) of carbohydrate digestion along their digestive tract. Alphaamylase activity and capacity is significantly higher in S. cretensethan U. scaber(p&lt;0.05). Activity in S. cretense is very high, comparable to levels reported for carp and tilapia. It is similar in anterior and posterior intestine, however, the posterior intestine comprises a more important role in alpha amylase capacity. In U. scaber, activity is present in pyloric caeca and intestine. Levels are very low, comparable to levels reported for other benthic marine carnivores. There is no difference between activities in intestine and pyloric caeca. However, activity is higher in the anterior part of the intestine, lower in the posterior intestine and absent in the stomach. Such information is thought to be beneficial for improving knowledge on the biology of the examined species, and the physiology of nutrition, as well as for assisting towards understanding these processes in other, more valuable species for aquaculture. Also, the possibility of using the stargazer alimentary tract, especially its pyloric caeca as a model system is discussed.

Occurrence of the Mediterranean parrotfish Sparisoma cretense (Perciformes: Scaridae) in south-eastern Apulia (south-east Italy)

The Mediterranean parrotfish Sparisoma cretense is reported for the first time along the south-eastern coasts of Apulia (Ionian Sea, south-east Italy). Only juvenile specimens of S. cretense were observed during visual census surveys carried out in late August 2000, whereas adults were never observed in, or reported from, this region. Juvenile parrotfish were 3–4-cm long (TL), with a light-grey livery, pale-yellow heads and marked yellow margins around the eyes. They were recorded at 5–15 m depth, whereas they were absent near the surface (0–2 m depth) and in deeper areas (25–28 m depth). The possibility that climatic changes occurring in the Mediterranean basin (i.e. water warming) would be involved in the spreading of S. cretense outside its typical distribution range is discussed.