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ERA5 reanalysis is used to examine extreme precipitation using a spatially dependent precipitation threshold applied within a cyclone compositing framework. This is used to account for regional variation in precipitation generating processes within Southern Hemisphere mid‐latitude cyclones across the cyclone lifecycle. The spatial extent of extreme precipitation is limited to a smaller region around the cyclone center compared to non‐extreme precipitation, though extreme precipitation displays a good spatial correlation with non‐extreme precipitation. Extreme precipitation occurs more often during the deepening phase of the cyclone before it reaches peak intensity. Precipitation occurrence at the 90th and 98th percentiles reduces to 46% and 30% of the deepening value across the cyclone lifecycle, averaged over the composite. Precipitation fraction at the 90th and 98th percentile reduces to 80% and 60% of the deepening value. Our methodology provides a quantitative assessment of precipitation extremes both spatially and temporally, within a cyclone compositing framework. Plain Language Summary: Extra‐tropical cyclones play a major role in the circulation within the atmosphere, acting to transfer heat toward the poles. Here we assess the representation of extreme precipitation within extra‐tropical cyclones. By applying a threshold for precipitation that changes with geographic location, we are able to determine how extreme precipitation varies within a cyclone‐centered coordinate system. When breaking cyclones into lifecycle stages representing deepening, peak intensity and decay, we find that extreme precipitation occurs most often as the cyclone is developing. The area of the cyclone relevant for extremes reduces toward the cyclone center as the threshold for determining extreme precipitation increases. Extreme precipitation weakens at a higher rate as cyclones becomes more intense, highlighting the importance of extremes in the growth phase of the cyclone. Key Points: We detail a new methodology to assess precipitation extremes within cyclone composites using a spatially dependent precipitation thresholdExtreme precipitation occurs preferentially and makes up a larger fraction of total accumulation before cyclones reach peak intensityExtreme precipitation is more constrained around the cyclone center and weakens more rapidly over time compared to moderate precipitation [ABSTRACT FROM AUTHOR]

1. Using 41 years of data, we examined annual variations in the reproductive performance of the red-billed gull at the Kaikoura Peninsula, New Zealand and related these to changes in climate, oceanography and the availability of the planktonic euphausiid Nyctiphanes australis, the bird's principal food. 2. In 1994 the population began to decline, and between 1983 and 2003 it was reduced by 51%. Adult non-breeders comprised an average of 32% of the population between 1983 and 1994, but following the decline they averaged only 18%. The age at recruitment changed markedly following the population decline: 27% of 2-year-old males bred for the first time prior to the decline, whereas the corresponding figure after the decline was 38%. The proportion of females commencing to breed as a 3-year-old was not significantly different before or after the decline. 3. An increase in the availability of euphausiids increased the likelihood of breeding and the recruitment of young individuals, caused earlier laying and resulted in an increase in the condition of adults, egg volume of gulls laying two egg clutches, clutch size and fledging success. 4. The relationship between food availability and the number of pairs that bred, laying date, clutch size and fledging success was significantly different prior to and after the population decline. The underlying cause appears to be a compensatory density-dependent mechanism that reduced interspecific competition for food. 5. The relative abundance of N. australis was correlated positively with the Southern Oscillation Index (SOI) and the frequency of occurrence of NE winds. The proportion of non-breeders and mean laying date were correlated negatively with the SOI, and mean egg volume of two egg clutches correlated positively with the SOI. 6. These results emphasize that availability of adult euphausiids is critical for red-billed gulls. We hypothesize that high primary productivity of inshore water near Kaikoura in winter, linked to a stable water column of coastal water and upwelling of additional dissolved inorganic nutrients, increases the availability of adult euphausiids to the red-billed gull as long as the coastal water is not replaced by offshore subtropical water intrusions of warmer, low-nutrient water. [ABSTRACT FROM AUTHOR]