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Rodent eradications are a useful tool for the restoration of native biodiversity on islands, but occasionally these operations incur non-target mortality. Changes in cereal bait colour could potentially mitigate these impacts but must not compromise the eradication operation. Changing bait colour may reduce mortality of Henderson crakes (Zapornia atra), an endemic globally threatened flightless bird on Henderson Island, Pitcairn Islands, South Pacific Ocean. Crakes had high non-target mortality in a failed 2011 rat eradication operation and consumed fewer blue than green cereal pellets. We examined which cereal bait properties influenced its acceptance by captive Pacific rats (Rattus exulans) on Henderson Island. We held 82 Pacific rats from Henderson Island in captivity and provided them with non-toxic cereal bait pellets of varying properties (blue or green, moist or dry). We estimated the proportion of rats consuming bait using logistic generalised linear mixed models. We found no effect of sex, females’ reproductive status, bait colour or bait moisture on rats’ willingness to consume baits. Rats’ bait consumption was unaffected by cereal bait properties (colour or moisture). The use of blue bait is unlikely to affect future eradication operational success but may reduce non-target mortality of Henderson crakes. Timing cereal bait distribution in relation to precipitation may also reduce crake mortality without compromising palatability to rats.

The Fourth Assessment Report of the IPCC (IPCC AR4) Working Group II (2007) identifies small island states as being among the most vulnerable countries of the world to the adverse impacts of climate change. Hay, el al.y (2003) in discussing the Pacific's observed climate noted that compared to earlier historical records during the twentieth century, the southern Pacific had experienced a significantly drier and warmer climate (by 15 percent and 0.8°C, respectively). The Central Equatorial Pacific is facing more intensive rain (about 30 percent) and a similarly hotter climate (0.6°C), and sea surface temperatures in both areas have increased by about 0.4°C. These conditions are linked to an increased frequency of El Nino episodes since the 1970s (without alternating La Nina events). Other studies show that climate projections for the South Pacific indicate warming of 0.8 to 1.8°C and precipitation changes that range from -8 to +7 percent by mid-century (Ruosteenoja, el ai, 2003). By the end of the century, projected warming is 1.0 to 3.1°C and precipitation changes range from -14 to +14 percent. Projections of globally averaged sea-level rise range from 0.18 m to 0.58 m in 2090-2099 relative to 1980-1999; while tropical cyclones are likely to become more intense, have higher peak wind speeds, and bring heavier rainfall (IPCC, 2007). Thus, it is clear that there are winners and losers when it comes to climate and food security with mostly the countries in the mid to higher latitudes benefiting from global warming and the small island countries of the Pacific in the warmer latitudes standing to lose the most. The IPCC has concluded that the mounting evidence shows that climate change is unequivocally happening and may worsen in future; there is a need to act urgently to minimize these impacts.