The Copepod/Artemia Trade-Off in the Culture of Long Snouted Seahorse Hippocampus guttulatus Jorge Palma, Ismael Hachero-Cruzado, Miguel Correia, José Pedro Andrade Fishes, 2026 This study evaluated the effects of copepod use and copepod conditioning strategies on the growth and survival of long-snouted seahorse (Hippocampus guttulatus) juveniles from 1 to 60 days post-parturition (DPP). Four dietary treatments were tested: Artemia enriched for 24 h with Isochrysis galbana (control), daily collected copepods, copepods unfed for 48 h, and copepods enriched for 24 h with I. galbana. Juveniles fed copepod-based diets exhibited significantly higher growth and survival (p < 0.05) than those fed enriched Artemia. Mean standard length increased from 1.3 ± 0.1 cm at release to 5.9 ± 0.2, 7.5 ± 1.4, 7.1 ± 1.2, and 7.3 ± 1.1 cm at 60 DPP for the enriched Artemia, daily collected copepods, unfed copepods, and enriched copepods treatments, respectively. Wet weight increased from 0.002 ± 0.001 g to 0.44 ± 0.07, 0.81 ± 0.40, 0.68 ± 0.30, and 0.76 ± 0.40 g, while final survival reached 20%, 60%, 33.3%, and 56%, respectively. Compared with enriched Artemia, copepod-based diets markedly enhanced juvenile performance, supporting faster growth and promoting favorable behavioral traits that contributed to improved survival. These results demonstrate that copepods constitute a superior live feed for early juvenile H. guttulatus; however, copepod conditioning strategies directly influence their nutritional quality and, consequently, seahorse growth and survival. The use of copepods throughout the first 60 DPP is therefore not only feasible but strongly recommended for optimizing juvenile H. guttulatus rearing performance.
Temperature Effects on Growth Performance, Fecundity and Survival of Hippocampus guttulatus Jorge Palma, Miguel Correia, Francisco Leitão, José Pedro Andrade Diversity, 2024 This experiment aimed to determine the temperature limits beyond which seahorse growth and reproduction become suboptimal due to climate change. Four temperatures (16, 20, 24, and 28 °C) were tested to evaluate their effect on juvenile (1–56 days post-parturition (DPP)) and adult (one year old) long-snout seahorses, Hippocampus guttulatus. Additionally, the reproductive performance of adults was observed. Another experiment measured oxygen consumption (MO2) in the same age groups and temperatures. Adults showed significantly higher growth rates at 20 and 24 °C compared to 16 and 28 °C. Adult mortality rates were 0%, 0%, 6.2%, and 62.5% at the respective temperatures. Juvenile growth performance was higher at 20 °C and 24 °C but significantly lower at 16 °C and null at 28 °C, with survival rates of 8%, 62%, 10%, and 0%, respectively. Oxygen consumption increased with temperature, ranging from 106.3 ± 3.1 to 203.3 ± 3.1 μmol O2/g BW/h at 16 °C, and from 127.6 ± 3.5 to 273.3 ± 3.1 μmol O2/g BW/h at 28 °C for adults and 1 DPP juveniles, respectively. The study highlights that juvenile and adult H. guttulatus have narrow thermal boundaries, beyond which reproduction, growth, and survival are seriously affected. Under climate change, the species appears unable to cope, potentially leading to their rapid disappearance.
Replacement of Fish Meal with Crustacean Meals in Diets for Long-Snouted Seahorse, Hippocampus guttulatus: Digestibility and Growth Performance Jorge Palma, Miguel Correia, José Pedro Andrade, Dominique Bureau Fishes, 2024 This study investigated the effect of partially replacing fish meal with krill and copepod meals in inert diets co-fed with shrimp on the growth and nutrient digestibility of long-snout seahorses (Hippocampus guttulatus). A control diet (Diet 1) using raw starch and four experimental diets with similar protein (≈44.8%) and energy (≈15.1 MJ/kg) levels were tested. Diet 2 used fish meal as the sole protein source, while in Diets 3–5, krill and copepod meals replaced 44% of the fish meal. Seahorses fed shrimp + Diets 2–5 showed significantly higher growth rates (p < 0.05) than those fed shrimp + Diet 1, though there were no significant growth differences among Diets 2–5. Digestibility of dry matter (46.1% to 72.2%), lipids (73.3% to 85.5%), crude protein (89.8% to 95.8%), energy (82% to 92.2%), and phosphorus (28.7% to 64.4%) varied with diet, being consistently lower in seahorses fed shrimp + Diet 1. As an agastric species, H. guttulatus did not exhibit impaired digestibility for any of the tested nutrients, minerals, or energy. This study suggests that crustacean meals can effectively substitute fish meal in inert diets for this species, contributing to the sustainability and optimization of captive seahorse husbandry practices.
Use of isotopic and elemental fingerprints for seahorse species discrimination and traceability of geographic origin Ana Elisa Cabral, Ricardo Calado, Jorge Palma, Fernando Ricardo, Eduardo Ferreira da Silva, et al. Frontiers in Marine Science, 2024 Seahorses (Hippocampus spp.; Family Syngnathidae) are mainly targeted by Traditional Chinese Medicine, curio and ornamental trade, as dried or live specimens. Traceability tools may help fill the gaps on supply chains, securing information on geographic origin and identification of traded specimens. Fin-clipping, a non-lethal and well-established method in seahorse research, offers a potential approach to trace the geographic origin and certify the aquaculture of these flagship species. As such, this study aimed to investigate the existence of differences in isotopic profiles of four seahorse species cultured at research centers located in southern Portugal and northern Spain, as well as between cultured Hippocampus guttulatus sourced from two research centers, and between wild and cultured specimens of this species. This research also evaluated the potential of combining isotopic and elemental fingerprints for seahorse species discrimination, through inductively continuous-flow isotope ratio mass spectrometry (IR-MS) and plasma mass spectrometry (ICP-MS). Species cultured at the same research centers exhibited similar stable isotope composition (δ13C and δ15N), except in the case of temperate H. guttulatus from northern Spain, which differed significantly from tropical species H. kuda and H. reidi. These differences could be due to phylogenetic dissimilarities and differences in seawater temperature. The δ15N composition allowed to discriminate between cultured H. guttulatus from the two research centers and between cultured and wild specimens. While dorsal fin isotopes alone did not prove to be a reliable tool for the discrimination of different cultured species, combining them with elemental profiles from seahorses’ whole-body allowed to successfully discriminate between H. kuda and H. reidi. This preliminary research demonstrates the potential of stable isotope and elemental analyses for tracing seahorses’ geographic origin and species identification. However, further research should be performed to validate these findings for wild specimens, particularly those from illegal, unreported and unregulated (IUU) fisheries and trade.
Optimization of Live Prey Enrichment Media for Rearing Juvenile Short-Snouted Seahorse, Hippocampus hippocampus Jorge Palma, Ricardo Lima, José Pedro Andrade, Maria João Lança Fishes, 2023 This study aimed to determine a nutritionally adequate feeding protocol for Hippocampus hippocampus juveniles. In the experimental trial, seahorses were fed copepods from 0–7 days post-parturition (DPP) and, from 8–28 DPP, four different dietary treatments: (copepods (control diet) (Cop); microalgae-enriched Artemia with a docosahexaenoic acid (DHA)/eicosapentaenoic acid (EPA) ratio of 2:1 (ArtDHA/EPA); microalgae-enriched Artemia with a DHA/EPA ratio of 2:1 along with 5% copepods (ArtDHA/EPA5%); and with 10% copepods (ArtDHA/EPA10%)). At the end of the trial, juvenile seahorses fed Cop grew significantly more (p < 0.05) (5.1 mg d−1) than those on fish-fed diets ArtDHA/EPA5% or ArtDHA/EPA10% (3.09 and 3.07 mg d−1, respectively), or those on the fish-fed ArtDHA/EPA (1.83 mg d−1) diet, all of which performed poorly. Data suggest that feeding copepods during the first 7 DPP promotes maturation of the digestive tract of juvenile seahorses, and the addition of a limited amount of copepods to the diet improves H. hippocampus juvenile growth performance when compared with the use of Artemia as a single diet due to the improvement of the essential fatty acid profile in the diets.
Lipid characterization of cultured Hippocampus hippocampus trunk muscles shed light over their functional potential AE Cabral, F Rey, J Batista, M Pinho, R Pais, T Sousa, J Palma, C Patinha, ... Applied Food Research, 101920 , 2026 2026
The Copepod/ Artemia Trade-Off in the Culture of Long Snouted Seahorse Hippocampus guttulatus J Palma, I Hachero-Cruzado, M Correia, JP Andrade Fishes 11 (2), 72 , 2026 2026
Effect of warming on European green crab (Carcinus maenas) populations from larvae to sexual maturity JN Monteiro, A Ovelheiro, L Sordo, J Palma, M Pinto, MA Teodósio, ... Journal of Experimental Marine Biology and Ecology 594, 152160 , 2026 2026
Collaborative bottom-up Trust Missions: a perspective on long-term strategies with and for people and Nature JL Pelegrí, N Bojanić, P Pinto, D Whyte, P Annasawmy, I Burgues, ... npj ocean sustainability 4 (1), 57 , 2025 2025
Predation success of declining long-snouted seahorse (Hippocampus guttulatus) population under habitat shifts F Parreira, J Palma, R Santos, B Martínez-Crego Marine Environmental Research 209, 107247 , 2025 2025 Citations: 1
Temperature Effects on Growth Performance, Fecundity and Survival of Hippocampus guttulatus J Palma, M Correia, F Leitão, JP Andrade Diversity 16 (12), 719 , 2024 2024 Citations: 2
Use of isotopic and elemental fingerprints for seahorse species discrimination and traceability of geographic origin AE Cabral, R Calado, J Palma, F Ricardo, E Ferreira da Silva, C Patinha, ... Frontiers in Marine Science 11, 1494320 , 2024 2024 Citations: 2
Replacement of Fish Meal with Crustacean Meals in Diets for Long-Snouted Seahorse, Hippocampus guttulatus : Digestibility and Growth Performance J Palma, M Correia, JP Andrade, D Bureau Fishes 9 (10), 383 , 2024 2024 Citations: 3
Climate Induced Temperature Effects on Growth Performance and Fecundity of Hippocampus guttulatus J Palma, M Correia, F Leitão, JP Andrade Preprints , 2024 2024
Use of isotopic fingerprints as traceability and species discrimination tools: seahorses as a case study AE Cabral, R Calado, J Palma, F Ricardo Research summit 2024-Book of abstracts, 430 , 2024 2024
Syngnathid fishes: biology, ecology, physiology, conservation and innovative rearing techniques M Planas, M Gristina, J Palma, G Qin, E Rose, O Roth, PR Teske Frontiers in Marine Science 10, 1309683 , 2023 2023 Citations: 2
Extensive gene loss parallels kidney aglomerulism in Syngnathidae B Pinto, AM Machado, JM Cordeiro, SM Kolbadinezhad, E Fonseca, ... Current Biology 33 (20), R1044-R1046 , 2023 2023 Citations: 2
Optimization of Live Prey Enrichment Media for Rearing Juvenile Short-Snouted Seahorse, Hippocampus hippocampus J Palma, R Lima, JP Andrade, MJ Lança Fishes 8 (10), 494 , 2023 2023 Citations: 5
Different behavioral strategies of two sympatric seahorses: habitat availability and increased density of Hippocampus guttulatus alter the behavior of Hippocampus hippocampus D Spatafora, M Gristina, F Quattrocchi, C Pierri, T Lazic, J Palma Frontiers in Marine Science 10, 1138296 , 2023 2023 Citations: 7
Fatty acid profiles of cultured Hippocampus hippocampus trunk muscles and potential nutritional value AE Cabral, F Rey, MR Domingues, M Cabral, M Planas, J Palma, ... Frontiers in Marine Science 10, 1135250 , 2023 2023 Citations: 6
Behavioral traits of captive short-snouted seahorse Hippocampus hippocampus, Linnaeus 1758 M Gristina, C Pierri, T Lazic, J Palma 2022 IEEE International Workshop on Metrology for the Sea; Learning to … , 2022 2022 Citations: 6
Impacts of pineapple peel powder on growth performance, innate immunity, disease resistance, and relative immune gene expression of Nile tilapia, Oreochromis niloticus H Van Doan, SH Hoseinifar, R Harikrishnan, T Khamlor, M Punyatong, ... Fish & Shellfish Immunology 114, 311-319 , 2021 2021 Citations: 76
Successful Use of Geochemical Tools to Trace the Geographic Origin of Long-Snouted Seahorse Hippocampus guttulatus Raised in Captivity AE Cabral, F Ricardo, C Patinha, EF Silva, M Correia, J Palma, M Planas, ... Animals 11 (6), 1534 , 2021 2021 Citations: 10
The paradox of retained genetic diversity of Hippocampus guttulatus in the face of demographic decline R Stacy, J Palma, M Correia, AB Wilson, JP Andrade, R Castilho Scientific Reports 11 (1), 10434 , 2021 2021 Citations: 3
A crown for each monarch: a distinguishable pattern using photo‐identification M Correia, D Antunes, JP Andrade, J Palma Environmental Biology of Fishes 104 (2), 195-201 , 2021 2021 Citations: 5
MOST CITED SCHOLAR PUBLICATIONS
The Atlantic–Mediterranean transition: discordant genetic patterns in two seabream species, Diplodus puntazzo (Cetti) and Diplodus sargus (L.) L Bargelloni, JA Alarcon, MC Alvarez, E Penzo, A Magoulas, J Palma, ... Molecular phylogenetics and evolution 36 (3), 523-535 , 2005 2005 Citations: 132
Impacts of pineapple peel powder on growth performance, innate immunity, disease resistance, and relative immune gene expression of Nile tilapia, Oreochromis niloticus H Van Doan, SH Hoseinifar, R Harikrishnan, T Khamlor, M Punyatong, ... Fish & Shellfish Immunology 114, 311-319 , 2021 2021 Citations: 76
Seahorse (Hippocampinae) population fluctuations in the ria Formosa lagoon, south Portugal M Correia, IR Caldwell, HJ Koldewey, JP Andrade, J Palma Journal of Fish Biology 87 (3), 679-690 , 2015 2015 Citations: 70
Growth and survival of adult long snout seahorse (Hippocampus guttulatus) using frozen diets J Palma, J Stockdale, M Correia, JP Andrade Aquaculture 278 (1-4), 55-59 , 2008 2008 Citations: 57
Influence of environmental factors and energetic value of food on Little Tern Sterna albifrons chick growth and food delivery VH Paiva, JA Ramos, T Catry, P Pedro, R Medeiros, J Palma Bird Study 53 (1), 1-11 , 2006 2006 Citations: 55
Effect of different Artemia enrichments and feeding protocol for rearing juvenile long snout seahorse, Hippocampus guttulatus J Palma, DP Bureau, JP Andrade Aquaculture 318 (3-4), 439-443 , 2011 2011 Citations: 52
Gastric evacuation and feeding in the gilthead sea bream reared under semi-intensive conditions J Pedro Andrade, K Erzini, J Palma Aquaculture International 4 (2), 129-141 , 1996 1996 Citations: 51
Identifying key environmental variables of two seahorse species ( Hippocampus guttulatus and Hippocampus hippocampus ) in the Ria Formosa lagoon, South … M Correia, HJ Koldewey, JP Andrade, E Esteves, J Palma Environmental Biology of Fishes 101 (9), 1357-1367 , 2018 2018 Citations: 49
Intercolony and annual differences in the diet and feeding ecology of little tern adults and chicks in Portugal T Catry, JA Ramos, VH Paiva, J Martins, A Almeida, J Palma, PJ Andrade, ... The condor 108 (2), 366-376 , 2006 2006 Citations: 47
Effects of binder type and binder addition on the growth of juvenile Palaemonetes varians and Palaemon elegans (Crustacea: Palaemonidae) J Palma, DP Bureau, JP Andrade Aquaculture International 16 (5), 427-436 , 2008 2008 Citations: 44
Can artificial holdfast units work as a habitat restoration tool for long-snouted seahorse (Hippocampus guttulatus Cuvier)? M Correia, J Palma, H Koldewey, JP Andrade Journal of Experimental Marine Biology and Ecology 448, 258-264 , 2013 2013 Citations: 43
The impact of dietary supplementation with astaxanthin on egg quality and growth of long snout seahorse ( Hippocampus guttulatus ) juveniles J Palma, JP Andrade, DP Bureau Aquaculture Nutrition 23 (2), 304-312 , 2017 2017 Citations: 41
The effect of diet on ontogenic development of the digestive tract in juvenile reared long snout seahorse Hippocampus guttulatus J Palma, DP Bureau, JP Andrade Fish physiology and biochemistry 40 (3), 739-750 , 2014 2014 Citations: 41
The effect of dietary sericite on growth performance, digestive enzymes activity, gut microbiota and haematological parameters of Nile tilapia, Oreochromis niloticus (L … MS Hassaan, EY Mohammady, MR Soaudy, J Palma, EE Shawer, ... Animal feed science and technology 262, 114400 , 2020 2020 Citations: 40
Effects of artificial holdfast units on seahorse density in the Ria Formosa lagoon, Portugal M Correia, H Koldewey, JP Andrade, J Palma Journal of Experimental Marine Biology and Ecology 471, 1-7 , 2015 2015 Citations: 39
Developmental stability and genetic heterozygosity in wild and cultured stocks of gilthead sea bream (Sparus aurata) J Palma, JA Alarcon, C Alvarez, E Zouros, A Magoulas, JP Andrade Journal of the Marine Biological Association of the United Kingdom 81 (2 … , 2001 2001 Citations: 33
The use of a non‐invasive tool for capture–recapture studies on a seahorse Hippocampus guttulatus population M Correia, J Palma, H Koldewey, JP Andrade Journal of Fish Biology 84 (4), 872-884 , 2014 2014 Citations: 31
Growth, Reproductive Performances, and Brood Quality of Long Snout Seahorse, Hippocampus guttulatus , Fed Enriched Shrimp Diets J Palma, JP Andrade, DP Bureau Journal of the World Aquaculture Society 43 (6), 802-813 , 2012 2012 Citations: 28
Effects of anthropogenic noise as a source of acoustic stress in wild populations of Hippocampus guttulatus in the Ria Formosa, south Portugal J Palma, M Magalhães, M Correia, JP Andrade Aquatic Conservation: Marine and Freshwater Ecosystems 29 (5), 751-759 , 2019 2019 Citations: 26
Advances in tagging syngnathids, with the effects of dummy tags on behaviour of Hippocampus guttulatus IR Caldwell, M Correia, J Palma, ACJ Vincent Journal of Fish Biology 78 (6), 1769-1785 , 2011 2011 Citations: 24