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The biological world is rapidly changing following decades of anthropogenic disturbances.Under these conditions, species with stable or increasing abundances have been described as winners with the potential for future success, but this assertion is unreliable without knowledge of the selective basis of winning. The incentive to find winners is acute for reef corals, for which large declines in abundance have motivated restoration efforts targeting winning corals. On Caribbean reefs, Porites astreoides has emerged as a potential winner, but the demographic basis of this categorization is poorly known. Here we test for demographic benchmarks of winning in this species by quantifying abundances and sizes of colonies over 28 yr on the south coast of St. John, US Virgin Islands. From 1992 to 2001, the density of colonies of P. astreoides showed little variation while colonies increased in size by 58%, but from 2002 to 2019, population density increased 2.7-fold, and colony size declined by 41%; accompanying these trends, the mean absolute cover of Porites spp. declined by 46% from 2010 to 2019. Low recruitment and rising abundances of colonies ≤4 cm diameter suggest that partial mortality and fission depressed colony sizes. The reversal over three decades of a positive demographic trend for a ubiquitous coral underscores the challenges of identifying winners from short-term population performance. Without a mechanistic understanding of fitness, the search for winners based on demographic trends may be futile.

On Caribbean reefs, colonies of the hydrocoral Millepora alcicornis are capable of pursuing and overgrowing arborescent octocorals (Wahle ). Nearly four decades since these interactions were described, we quantified arborescent octocorals encrusted by Millepora spp. (Linnaeus 1758) on shallow reefs in St. John, U.S. Virgin Islands, and evaluated encrusted colonies for evidence of an origin through pursuit. In 2014, 8% of octocorals (n=1684 colonies) were encrusted by Millepora spp., and in 2015, 12% were encrusted (n=847 colonies). Millepora spp. encrusted colonies of 10 octocoral genera, and in 2014, the most frequently encrusted were Eunicea spp. (40% of encrusted octocorals); in 2015, the most frequently encrusted were Gorgonia spp. (46% of encrusted colonies). In both years, ≥67% of encrusted octocorals were >21 cm from other colonies of Millepora spp.; 7% of octocorals were >1.3 m from colonies of Millepora spp. in 2014; and 16% of octocorals were >2.0 m from colonies of Millepora spp. in 2015. Relative to the ~5% of octocorals encrusted by Millepora spp. in Jamaica in the late 1970s, a high percentage (~9%) of octocorals were encrusted by Millepora spp. in St. John in 2014 and 2015. The large distances from most encrusted octocorals to the nearest colonies of Millepora spp. in St. John are inconsistent with a hypothesized origin through pursuit, contact, and overgrowth (sensu Wahle ).

K–12 science programs in the United States are implementing inquiry-based lessons to expose students to the scientific process, and in some states these changes are mandated by regulations. At the same time, university faculty in science, technology, engineering, and math (STEM) disciplines are being encouraged by agencies funding their research to develop outreach activities that typically involve schools. Outreach programs promoting interactions between schools and universities are one means to address this need, and here we describe such a program between a Los Angeles independent school and California State University, Northridge. Our program exploits experiential learning focused on marine biology to engage students in ecological research with application to contemporary environmental issues such as climate change. Moreover, it addresses multiple aspects of the Next Generation Science Standards within a flexible framework that can be adapted to multiple curricular needs. Coral reefs are used as a model system in this program, but the concepts can easily be extended to other coastal marine environments. The program has evolved through three phases: (1) fostering interactions among educational partners, and developing curricula through research that exploits problem-solving skills; (2) completion of scientific activities in the classroom and field; and (3) engaging students in the scientific process through professional conferences and publication. These efforts have led to a self-sustaining program of interactions among schoolchildren, undergraduates, graduate students, K–12 educators, and university faculty that is promoting STEM careers and generating peer-reviewed publications.

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