Cetacean Stranding Response Program and Spatial-Temporal Analysis in Taiwan, 1994-2018.

A national cetacean stranding response program in Taiwan has evolved significantly in the past three decades. Initially co-ordinated by National Taiwan University from 1994, the program transitioned to the Taiwan Cetacean Society in 1999, and local governments took on a more prominent role after 2009. A comprehensive stranding database (1994-2018) has been maintained, which documented 1320 stranding events involving 1698 animals from at least 27 species. The most commonly stranded species include finless porpoises, bottlenose dolphins, Kogia spp., and Risso's dolphins. The stranding rates varied annually and seasonally, with increases noted from an average of 16 events per year for the first 3 years to 44-58 events per year between 1997 and 2015, and a sharp rise to over 90 events per year for the period of the last three years. Seasonal variations were also significant, with higher stranding rates during the northeastern monsoon (NEM, October to next April) than that during southwestern monsoon (SWM, May to September). From the aspect of distribution, more frequent and even strandings occurred along the coast of northern Taiwan, while mass strandings were concentrated in the southwestern counties during NEM. Among all strandings, 390 events (29.5%) and 660 animals (38.9%) were live ones. Under great effort in rescuing and rehabilitating 52 cases, 15 cetacean individuals have been released since 2000. Additionally, there have been 56 mass strandings involving at least 11 species since 1994, predominated by pygmy killer whales, particularly during the NEM season along the southwest coast. This study not only contributes to our understanding of the stranding patterns and diversity of the cetaceans in Taiwan, but also provides valuable insights for future conservation strategies on cetaceans in the western Pacific.

Tail loss compromises immunity in the many-lined skink, Eutropis multifasciata.

Tail autotomy incurs energetic costs, and thus, a trade-off in resource allocation may lead to compromised immunity in lizards. We tested the hypothesis that tailless lizards will favor constitutive innate immunity responses over an energetically costly inflammatory response. The influence of fasting and colorful ornamentation was also investigated. We experimentally induced tail autotomy in the lizard Eutropis multifasciata and found that inflammation was suppressed by tail loss, but not further affected by fasting; the suppressive effect of colorful ornamentation was manifested only in males, but not in females. Constitutive innate immunity was not affected by any of these factors. As expected, only costly inflammation was compromised, and a less expensive constitutive innate immunity might be favored as a competent first-line defense during energetically demanding periods. After considering conventional trade-offs among tail regeneration and reproduction, further extending these studies to incorporate disease risk and how this influences escape responses to predators and future reproduction would make worthwhile studies.

Morphological variations in a widely distributed Eastern Asian passerine cannot be consistently explained by ecogeographic rules.

Ecogeographic rules that describe quantitative relationships between morphologies and climate might help us predict how morphometrics of animals was shaped by local temperature or humidity. Although the ecogeographic rules had been widely tested in animals of Europe and North America, they had not been fully validated for species in regions that are less studied. Here, we investigate the morphometric variation of a widely distributed East Asian passerine, the vinous-throated parrotbill (Sinosuthora webbiana), to test whether its morphological variation conforms to the prediction of Bergmann's rule, Allen's rules, and Gloger's rule. We at first described the climatic niche of S. webbiana from occurrence records (n = 7838) and specimen records (n = 290). The results of analysis of covariance (ANCOVA) suggested that the plumage coloration of these parrotbills was darker in wetter/warmer environments following Gloger's rule. However, their appendage size (culmen length, beak volume, tarsi length) was larger in colder environments, the opposite of the predictions of Allen's rule. Similarly, their body size (wing length) was larger in warmer environments, the opposite of the predictions of Bergmann's rule. Such disconformity to both Bergmann's rule and Allen's rule suggests that the evolution of morphological variations is likely governed by multiple selection forces rather than dominated by thermoregulation. Our results suggest that these ecogeographic rules should be validated prior to forecasting biological responses to climate change especially for species in less-studied regions.

Cranial variation in the pantropical spotted dolphin, Stenella attenuata , in the Pacific Ocean.

Cranial variation in 129 pantropical spotted dolphins (Stenella attenuata) from the western and eastern tropical Pacific was investigated morphometrically. This study revealed significant sexual dimorphism in the dolphin skulls. Differences between the genders were mostly recorded in the rostrum and braincase, which are wider and more robust in males. This sexual variation was interpreted in terms of differences in behavioral and life-history strategies between genders. Geographical variation among populations of the eastern tropical Pacific (ETP), Japan, and Taiwan was also significant, with different sexual patterns. While no clear trend in geographical variation was detected in males, there was a positive relationship in females between morphological differences and geographical distance. That is, Japanese and Taiwanese female specimens were morphologically more similar than revealed by other pairwise comparisons between them and the ETP specimens. Moreover, two canonical discriminant functions further discriminated the three populations for males and females, respectively. The two functions showed that the rostrum and braincase are the principal elements in discrimination of geographical variation in males, while only the rostrum is the major discriminant morph of geographical variation in females. In addition, tests based on Mahalanobis distance-squares were conducted to assign six specimens from the western tropical Pacific to the above three populations to clarify the similarities among them.

Himalayan black bulbuls (Hypsipetes leucocephalus niggerimus) exhibit sexual dichromatism under ultraviolet light that is invisible to the human eye.

Sexual dichromatism is a key proxy for the intensity of sexual selection. Studies of dichromatism in birds may, however, have underestimated the intensity and complexity of sexual selection because they used museum specimens alone without taking colour-fading into account or only measured conspicuous visual traits in live animals. We investigated whether the Himalayan black bulbul (Hypsipetes leucocephalus nigerrimus), which is sexually monomorphic to the human eye, exhibits sexual dichromatism distinguishable by a spectrometer. We measured the reflectance (within both the human visual perceptive and the ultraviolet ranges) of two carotenoid-based parts and eight dull and melanin-based parts for each individual live bird or museum skin sampled. According to an avian model of colour discrimination thresholds, we found that males exhibited perceptibly redder beaks, brighter tarsi and darker plumage than did females. This suggests the existence of multiple cryptic sexually dichromatic traits within this species. Moreover, we also observed detectable colour fading in the museum skin specimens compared with the live birds, indicating that sexual dichromatism could be underestimated if analysed using skin specimens alone.

The complete mitogenome of Ginkgo-toothed beaked whale (Mesoplodon ginkgodens) (Chordata: Ziphiidae).

In this study, we used the next-generation sequencing method to deduce the complete mitogenome of Ginkgo-toothed beaked whale (Mesoplodon ginkgodens) for the first time. The nucleotide composition was asymmetric (33.3% A, 25.3% C, 12.6% G, and 28.7% T) with an overall GC content of 37.9%. The length of the assembled mitogenome was 16,339 bp and follows the typical vertebrate arrangement, including 13 protein coding genes, 22 transfer RNAs, 2 ribosomal RNAs genes, and a non-coding control region of D-loop. The D-loop contains 870 bp and is located between tRNA-Pro and tRNA-Phe. The complete mitogenome of Ginkgo-toothed beaked whale deduced in this study provides essential and important DNA molecular data for further phylogenetic and evolutionary analysis for cetaceans.

A molecular forensic method for identifying species composition of processed marine mammal meats.

We used universal primers designed for the cytochrome oxidase I (CO I) sequence of the order Cetacea and the family Phocidae to prove that meat fritters sold in Taiwan contained meat from two seal, six cetacean, and one pig species. The sequence information for CO I obtained in this study was limited and population genetics data for the eight sampled marine mammalian species was insufficient to deduce where these marine mammals were hunted. Regardless of the geographic origins of the marine mammal flesh, sale and consumption of marine mammals in Taiwan violates the Wildlife Conservation Act. This study provides PCR primers that could enable government testing of suspect meats to curtail the illegal trade in marine mammal products.

The de novo assembly of mitochondrial genomes of the extinct passenger pigeon (Ectopistes migratorius) with next generation sequencing.

The information from ancient DNA (aDNA) provides an unparalleled opportunity to infer phylogenetic relationships and population history of extinct species and to investigate genetic evolution directly. However, the degraded and fragmented nature of aDNA has posed technical challenges for studies based on conventional PCR amplification. In this study, we present an approach based on next generation sequencing to efficiently sequence the complete mitochondrial genome (mitogenome) of two extinct passenger pigeons (Ectopistes migratorius) using de novo assembly of massive short (90 bp), paired-end or single-end reads. Although varying levels of human contamination and low levels of postmortem nucleotide lesion were observed, they did not impact sequencing accuracy. Our results demonstrated that the de novo assembly of shotgun sequence reads could be a potent approach to sequence mitogenomes, and offered an efficient way to infer evolutionary history of extinct species.