This study investigated blubber morphology and correlations of histological measurements with ontogeny, geography, and reproductive state in live, wild bottlenose dolphins (Tursiops truncatus) from the southeastern United States. Surgical skin-blubber biopsies (N=74) were collected from dolphins during capture-release studies conducted in two geographic locations: Charleston, SC (N=38) and Indian River Lagoon, FL (N=36). Histological analysis of blubber revealed stratification into superficial, middle, and deep layers. Adipocytes of the middle blubber were 1.6x larger in Charleston subadults than in Indian River Lagoon subadults (4,590+/-340 compared to 2,833+/-335 microm2 per cell). Charleston subadult dolphins contained higher levels of total blubber lipids than Charleston adult animals (49.3%+/-1.9% compared to 34.2%+/-1.7%), and this difference was manifested in more adipocytes in the middle blubber layer (19.2+/-0.9 compared to 14.9+/-0.5 cells per field). However, dolphins from Indian River Lagoon did not exhibit this pattern, and the adipocyte cell counts of subadults were approximately equal to those of the adults (16.0+/-1.4 compared to 13.4+/-0.8 cells per field). The colder year-round water temperatures in Charleston compared to Indian River Lagoon may explain these differences. Adipocytes in the deep blubber layer were significantly smaller in lactating and simultaneously pregnant and lactating animals compared to pregnant dolphins (840+/-179, 627+/-333, and 2,776+/-586 microm2 per cell, respectively). Total blubber lipid content and adipocyte size in the deep blubber of mothers with calves decreased linearly with calf length. Lactating females may utilize lipids from the deep blubber during periods of increased energetic demands associated with offspring care. This study demonstrates that ontogeny, geography, and reproductive state may influence morphological parameters such as structural fiber densities and adipocyte numbers and sizes, measured in bottlenose dolphin blubber.

Long-term acoustic recorders (black instrument in figure) can be used to estimate spawning timelines and rhythms by detecting fish calls associated with courtship. Design by Tim Devine, USCB Graphics ManagerMar Ecol Prog Ser 581: [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19] 2017 2015). In the family Sciaenidae, sound-producing fishes include Atlantic croaker Micropogonias undulatus, silver perch Bairdiella chrysoura, black drum Pogonias cromis, spotted seatrout Cynoscion nebulosus, weakfish C. regalis, red drum Sciaenops ocellatus, spot Leiostomus xanthurus, and southern kingfish Menticirrhus americanus (Luczkovich et al. 1999, Sprague 2000, Ramcharitar et al. 2006, Gannon & Taylor 2007, Lowerre-Barbieri et al. 2008, Walters et al. 2009, Tellechea et al. 2011, Montie et al. 2015. Sound production in these fishes typically involves rapid movement of the sonic muscle surrounding the swim bladder. The resulting calls are species-specific due to anatomical differences in swim bladder and sonic muscle morphology as well as neural programming; therefore, call types can be used for species identification (Winn 1964, Ramcharitar et al. 2006.Sound production in fish species has been associated mainly with courtship behavior and reproduction (e.g. Saucier & Baltz 1993, Mann & Lobel 1995, Luczkovich et al. 2008, Walters et al. 2009, Mann et al. 2010, Montie et al. 2016, 2017. Studies have recorded underwater sounds during spawning seasons and have shown that patterns of peak calling coincide with patterns of reproductive senescence (i.e. gonadosomatic indices, sperm motility, and plasma androgen levels; Connaughton & Taylor 1995). Other wild studies have simultaneously collected acoustic recordings and plankton tows, and these data have shown that fish calling and spawning are tightly associated (Mok & Gilmore 1983, Saucier & Baltz 1993, Luczkovich et al. 1999, Aalbers & Drawbridge 2008, Lowerre-Barbieri et al. 2008. For example, the timing and amount of calling in wild weakfish were positively correlated with the timing and numbers of sciaenid eggs collected (Luczkovich et al. 1999). Similar findings have been observed in captive studies (Guest & Lasswell 1978, Connaughton & Taylor 1996, Lowerre-Barbieri et al. 2008, Montie et al. 2016, 2017. In weakfish held in laboratory tanks, courtship behavior, male calling, and spawning were correlated (Connaughton & Taylor 1996). In a quantitative study with captive red drum, findings revealed that spawning was more productive when the amount of calling increased; more eggs were collected when calls were longer in duration and contained more pulses (Montie et al. 2016). In a similar study with captive spotted seatrout, spawning was more likely to occur when male fish called more frequently; a positive relationship was found between sound pressure levels in tanks and the number of eggs collected (Montie et al. 2017). These findings indicate that acoustic metrics can accurately predict spawning potential for some soniferous fishes and that deployment of lon...

The California sea lion (Zalophus californianus) has been a focal point for sensory, communication, cognition, and neurological disease studies in marine mammals. However, as a scientific community, we lack a noninvasive approach to investigate the anatomy and size of brain structures in this species and other free-ranging, live marine mammals. In this article, we provide the first anatomically labeled, magnetic resonance imagingbased atlas derived from a live marine mammal, the California sea lion. The brain of the California seal lion contained more secondary gyri and sulci than the brains of terrestrial carnivores. The olfactory bulb was present but small. The hippocampus of the California sea lion was found mostly in the ventral position with very little extension dorsally, quite unlike the canids and the mustelids, in which the hippocampus is present in the ventral position but extends dorsally above the thalamus. In contrast to the canids and the mustelids, the pineal gland of the California sea lion was strikingly large. In addition, we report three-dimensional reconstructions and volumes of cerebrospinal fluid, cerebral ventricles, total white matter (WM), total gray matter (GM), cerebral hemispheres (WM and GM), cerebellum and brainstem combined (WM and GM), and hippocampal structures all derived from magnetic resonance images. These measurements are the first to be determined for any pinniped species. In California sea lions, this approach can be used not only to relate cognitive and sensory capabilities to brain size but also to investigate the neurological effects of exposure to neurotoxins such as domoic acid. Anat Rec, 292:1523Rec, 292: -1547Rec, 292: , 2009